Several times in this Instructable, I'll be referencing the How-To: Make a Wii laptop page by Benjamin Heckendorn (thanks!). He has some VERY good tips on complete Wii disassembly as well as de-soldering.
Here are the tools you'll need:
A Wii (duh!)
An original NES
Small Phillips screw driver
De-soldering braid or de-soldering iron
Hot glue gun
Dremmel tool or drill with a fine tip drill bit (1/16" and large drill bit (5/16")
Wire (preferably multiple colors, I used 18AWG, but probably should have gone thinner in retrospect)
SD Reader you don't mind destroying (or SD port ordered online)
2 momentary switches (preferably 'micro' switches)
Step 1: Disclaimer
I hold no responsibility for broken parts, things not working, damage to your console, or anything else should you attempt this project.
I consider myself to have great soldering skills, and have worked with small electronics (read in: 30AWG wiring) in the past. If you are uncomfortable with [de]soldering fine electronics, I would recommend having someone else solder for you, or put this project off until your more familiar with this type of work.
*When I first started this project, I had no way to take pictures of my progress. I will try to be as detailed as possible for the first few steps.
Step 2: Disassemble Both Systems
IMPORTANT: Do not discard any of the Wii case components! You'll need them for various parts of the project later on.
Next, disassemble your NES console. Anyone who's taken something apart before, this should be cake! There's 6 Phillips screws all together on the under side of the NES. Put them aside for now. Once the case is open, remove all the screws for all the components (including the cart holder, power/reset buttons, controler ports, main board, and metal casing). Unhook the Power/Reset buttons from the main board and set them aside. The rest of the internal components can be discarded.
Step 3: Cutting the NES to Accomodate
Start with the bottom half of the NES case. I used a 5/16" drill bit to drill down all the screw holes OTHER THAN the ones that hook the bottom half to the top half and the ones for the Power/Reset switch (a Dremel tool/cutter would have been more efficient, but there wasn't one available at the time I did this project).
Remove the bottom cover, and cut out the expansion slot plate (y'know, if you wern't like me and didn't do it 20 or so years ago). From here, you need to sand down so everything is fairly even with the raised up sections (again, except where the power/reset switches are).
At this point, you should be able to take the more flat portion of the Wii case (picture #2 below) and set it inside the NES, and it will lay flat.
Now, we need to make sure we can put the expansion slot cover back on:
Place the flat section of the Wii case on the bottom of the NES with the screw holes up, the controller ports facing the back end of the NES, and the place the battery goes toward the front.
NOTE: In the picture below, it's showing the Wii case as far back and to the left as possible. This is incorrect (as I found out later on)! To see how much room you will need, place the Wii motherboard on this plastic piece, attach the DVD drive flexible flat and power cables, put the top of the NES on, and verify both cables reach where the DVD drive will go (about the center of the NES flap).
Orient the Wii case as far back as it can go (level with the A/V and power port holes) and about 3/4" from the left side (assuming the power/reset switch holes are away from you). While holding the Wii case in place, flip over the NES and draw a mark around where the expansion cover clips in. Using your drill or Dremel, cut out these small rectangles. Now (if all went well) you should be able to place the expansion slot cover back onto the NES and have it clip to the inside of the Wii case.
Step 4: The DVD Drive and Power Button
This was one of my first steps, so unfortunately, I don't have much in the line of pictures for this section (other than the completes below).
There is a black piece that held the DVD drive to the top of the Wii case. You'll have to screw this back into the DVD drive (this is the piece with the rubber around the screws that allow for vibration). There is a bit of overlap of this piece with the physical moving parts that eject/retract the DVD that you'll have to cut off as well (see the picture below). The mounting procedure is very complex: for me it involved lots of electrical tape!!! Oh, and re-enforcing it with hot glue...
Step 5: The Power/Reset Buttons and an LED
Because I didn't feel like re-wiring the power light on the Wii, I decided to make the light on the NES the DVD drive light (besides, I think it looks cooler). To start, take apart the front bezel from the Wii, and de-wire the two circuits on either side. Next, on the NES cut the connectors of the LED at the base of the power switch. It should be able to slide right out now. Take the 2 LED circuits from the Wii, put them on top of each other with a piece of electrical tape between them (LEDs on the outside), and shove them in the place the old LED was. It's a tight fit, but once it's closed, no one will know the difference!
Step 6: De-soldering (not for the Feint of Heart)
Now, for ME, this was the fun part! De-soldering all the main components from the Wii main board. To start, cut the piece of plastic between the Game Cube controller ports 2 and 3. Ports 3 & 4 I left attached to the board (after all, the NES only has 2 controller ports anyway!). Here is what you need to de-solder and detach from the main board:
Game Cube controller ports 1 & 2
Game Cube Memory Card ports (probably the most difficult for me)
A/V and Wii-mote port
SD slot (NOTE: initially, I DIDN'T detach this. It caused me more headaches after the fact.)
Once you have all the connectors detached from the Wii main board, you can put the board aside for now.
Next, I moved on to my SD reader. You can pick up just an SD slot online from someone like Digikey, however I wasn't in the mood to wait for shipping, and I had a spare laying around. Most are held together with 1 or 2 screws or a plastic clip. The part you need to de-solder is the SD holster and the pin connectors. If you can find one without the extra pins attached to check for the 'Lock', even better!
Side note: If you plan on saving yourself some trouble with re-soldering the Gamecube memory card ports (by the end of the project, I completely forgo these in the name of aesthetics) and wish to use the SD/Gamecube mod, now would be a good time to solder the necessary wires.
Step 7: Cutting NES to Fit
On the side, you'll also want to cut down either the Audio or Video ports to square them off so the USB ports can fit in.
The controller ports were a bit of a tight fit... Unscrew the 2 screws holding down the NES controller ports (if you haven't already). This should allow you to remove the current two ports. From the Wii parts pile, you should have a thin, black piece of plastic that designates the Game Cube ports. Cut out 2 of these holes completely without destroying the circle. Cut these two down so they can fit side-by-side behind the 1 and 2 controller port holes. Make sure they fit without much overlap and verify by placing the controller ports back on the NES (the plastic should snugly fit between the black and gray plastics). Once you verify they work, use your hot glue gun and a VERY THIN application, glue the holes into place. Additionally, while the glue is still hot, screw the black plastic piece back to the main NES case. You'll have a very slight overlap of the flat NES controller port over the hole. This is OK, as the Game Cube doesn't use the full size of the hole.
Step 8: Wire Your Wii!
I ended up soldering every pin on all connectors to every point on the Wii, which (in retrospect) wasn't the most efficient way to do this... It didn't occur to me to Google search the pinouts and find out only the necessary points needed for functionality (hint hint). Also, using only green wires probably wasn't the smartest thing on my part either...
Make sure you have roughly 6-8" length for each wire you use. The longest connection is going to be that of the controller ports. You may want to make sure the wire is long enough to reach from the back of the Wii to the front of the NES when the main board is in the case.
You can start with the SD connector. Most are easy to solder to (depending on how it was removed from the original casing).
I moved on to the connector pins on the Wii components, soldering a wire to each pin of all the connectors. Once I had all the connectors wired, I used the hot glue gun to re-enforce the connections.
Now to put it all together. Follow the wires and solder them to the appropriate places on the Wii main board. Everything gets soldered directly to the top of the board the components were de-soldered from.
Now, the NES Power/Reset buttons. Cut the connector off the end and strip down a bit of each wire. I'm not sure if N* changed their wire colors, but on mine, it worked like this:
The other 2 wires can be cut at the PWR/Reset button board, as they're for the LED we cut out earlier. Although it's not necessary to detach the original buttons from the Wii, it may make soldering easier for you. On the buttons on the main board, you'll see 3 pins each. When soldering onto them, you can choose either of the outside pins (the center pin is required). Solder the Red/Brown wires to the top button, and the yellow/orange wires to the next button down.
The third button would solder to one of your momentary buttons for 'sync' (I used a red button to distinguish between that and the eject buttons. Also, make sure you have long enough wire to wrap around the Wii to the bottom of the NES case on your sync button, as this is the mounting place.) The bottom most button should be your eject button.
The SD pins 1-9 should then be soldered directly to the Wii main board (they are conveniently labeled too!). Also, solder a lead wire to the pin marked 'CD', 'CD/WP' (circled in yellow below) and the unlabeled one at the bottom (circled in pink below). These points are what the Wii uses to test if there's a card inserted and if the write protect is on. In my case, I simply shorted the 'CD/WP' wire with the blank terminal (I can write to ANY card, regardless of the write protect tab). Finally, solder a toggle switch to the end of the CD and CD/WP wires. Feel free to add a 2nd switch for the CD/WP and blank terminal wire (on=read/write, off=read only) or attach it to the CD/WP wire (always read/write regardless).
The final place to hook wires up to would be the + and - of the battery terminal.
After you get all the components soldered into place, it's a good time to hook it up to the TV and verify you don't have a fried Wii, and all your switches work. Simply put the processor heatsink back into place, put the wifi/bluetooth adapters back in, hook up everything, and press the NES power button. If the light turns to green, and you have a display, working Wii-mote, working reset button, can read/write to the SD card, working WiFi, and have working Gamecube controlers, I'd say you should be good to go (and actually better off than my first 2 attempts)!
Go ahead and unhook everything, then you can re-enforce the joints with hot glue to make sure nothing comes loose.
Step 9: Cut/Mount Everything 1
The first (and easiest) should be the original battery holder from the Wii. Cut off the end with the screw. Now, drill a small hole (should be JUST larger than the wire used for the battery wires soldered earlier) through the top and side of this. The way this piece is designed, you can (and should) have a piece of plastic between the two drilled holes.
Next, move onto the outside part of the Wii case. The section that has to be cut out from this is about a 2" square around where the battery would normally be inserted. This allows for the underside wiring (battery, sync switch, SD slot) to wrap around the motherboard to the bottom port of the NES case. To ensure you cut enough, place the Wii panel inside the NES case (fitted like in step 3) and ensure you can see the 'Expansion Port' hole with enough room to fit 15-ish wires. Also, the exact opposite side should be either cut out completely, or have squares cut into it to accommodate for the Power and A/V ports (see * below)
Once you have the plastic fitted, move onto the metal main board mount (see pic below). Cut accordingly.
Finally, the large metal piece that covers the Wii main board should also be cut. To ensure the Wii got enough cooling, I cut it to fit JUST over the Bluetooth adapter and the processor. Place the heatsink onto the processor, put this metal piece back into place, and trace where you will cut with a magic marker (see below).
On the bottom of the NES case, drill a small hole for the sync button and the SD card switch[es]. Verify your switch[es] and/or button can fit through the hole before you proceed. Assuming you used the same style micro-button for the eject button, also drill a hole DIRECTLY in front of the DVD drive (see below). With the button inserted, the top flap should still be able to close. BE SURE YOU DON'T ACCIDENTALLY DRILL INTO THE DVD DRIVE ITSELF!!! (NOTE: this button should NOT be mounted yet)
Once you have all this cut out, it's time to start the mounting process. Start with mounting your SD switch[es] and sync button to the holes drilled. Next, string your SD port and battery terminal wires through the 'expansion slot'. Once these wires are in place (we do this now to avoid having to pull/tug on wires after everything is secured), secure the Wii panel to the underside of the NES case using 3-4 of the multitude of tiny phillips screws from dismantling the Wii. These can 'drill' directly to the path carved into the NES case. Once this is secured, place the bottom metal panel on top of that (it should more-or-less 'fall' into place). Now, the main board should also 'fall' into place (if you left Gamecube ports 3 & 4, they should line up with the crevasses at the top, see **).
If everything fits and all the screw holes line up, you're doing good so far. Now you can screw the Power/Reset buttons back into the front of the NES (one screw may be covered by your DVD drive LEDs, this is OK, as a single screw will secure it). Take the metal piece you cut earlier and place it on the main board. Any screw hole that ISN'T covered can be screwed in, thus securing the motherboard to the NES case.
Step 10: Cut/Mount Everything 2
Once you have the battery terminals all set, move on to the SD slot. I used hot glue (for lack of anything else) to secure the SD slot to the underside of the NES. Once secured, I also put a piece of electrical tape over it (to ensure the battery contacts don't touch the SD contacts). Now, you should be able to 'mount' (read in: heavily glue) the battery terminal to the top of the SD card as seen below.
Again, when inserting the battery (with the bottom of the NES facing you), the positive should be facing you, and the negative facing the top of the NES case.
Step 11: Cut/Mount Everything 3
These in place, you can replace whats left of the metal piece covering the Bluetooth adapter. Re-attach the Wii fan, and screw in any screws to secure these pieces to the Wii case.
Now that the main board is mounted, you can move on to the components. I had no other way to secure the AV/Remote, power, USB, and Gamecube ports other than hot glue. Use a liberal amount of glue all around to secure these into place.
The 2 circuit boards for the antenna are hot-glued to the inside of the NES case.
All the ports secured into place, now's a good time for your dry-run before the final assembly. Take the flexible flat and power cables, hook them up to the Wii motherboard and the DVD drive. Plug in all wires, cross your fingers, and press the power button. With any luck, you'll see what I saw below! Put a Wii game in, make sure it reads it, eject it, read/write the SD card, try the reset, power, and sync buttons, use the Gamecube functions, and try the WiFi. If something isn't working, double-check all your connections (a multi-meter helps here).
If you verify everything is running as it should, power it down and unhook it from the TV. If you have enough room (I didn't), go ahead and mount the eject button on the top of the NES case (the hole we drilled in front of the DVD drive). If not, unhook the DVD drive from the motherboard, then attach the eject button.
One of the hardest parts for me was re-attaching the flexible flat cable. Like I said in step #3, I mis-mounted the motherboard too far right, and the cable didn't reach the DVD drive originally. A quick search online, I was able to order one slightly longer than the original, and I was good to go!
Step 12: Close It All Up!
Congratulations! It's a lot of work, but for an awesome NES-looking Wii, it doesn't get much more authentic!
Step 13: If I Could Do It All Over Again...
This project took me almost a year to complete (on and off in my limited free time). When I started it, I had absolutely no clue how I would finish it or even what my next step would be. Most of the time, I made the steps up as I went and worked on trial and error. Certain steps, like the original SD slot removal, I initially tried to avoid, intending on having the SD card strictly internal. Also, my first go around, I accidentally swapped ports 1 and 2 on the front of the NES for Gamecube ports 2/1.
If anyone does attempt this project, I wish you the best of luck! If you need clarification on anything, or need any tips, feel free to contact me: firstname.lastname@example.org