For this Instructable, I'm going to use my truck, a 1999 Dodge Ram 2500 extended cab. I really despise the look of the yellow interior lights which is why I've decided to go with the LED lights.
/ / / / / / WARNING \ \ \ \ \ \ \
I AM NOT RESPONSIBLE FOR ANY DAMAGE TO YOUR VEHICLE, OR ANY BODILY HARM YOU MAY INFLICT.
Step 1: Tools Needed
1 Flat Head Screwdriver
2 Packs of 906 LED's or however many your vehicle needs.
1 Sharp Knife
I think the screwdriver came from Harbor Freight with five others for about $5. The screwdriver needs to be slim enough to fit the gap in the lights.
The LED's I found at O'Reillys one day.
The knife is a Kershaw Tone. I bought it at Academy the other day for about $26. It's really sharp and has the SpeedSafe Assisted Opening.
Step 2: Front Disassembly
To get these light covers off, you need to use your flat head screwdriver, and stick it in the outer most side to pry hook out. Once you get the hook off, you can pull it either left or right to get it out all the way. To get the light out, you need to pull it straight out, then kinda pull it down at an angle. Once it's out, you can cut open your LED package and put the first LED in! This particular LED light has 9 white LED's in it. In other words, bright! One thing the guy at the cash register told me is the light has polarity, so if it doesn't work one way, flip it over and it should work then. Once they both are installed and work, you can put your covers back on and move on to the light in the back.
Step 3: Rear Disassembly
On this cover, its a little tighter, but you shouldn't be able to break it. It's got two tabs that hold it up, so get those and it should pull down. Now stick your hand behind the whole assembly and pull it down and towards you, it should all come down. Turn it over and unclip the clear cover so it's easier to get the light out and put the new one in. Pull the old bulb straight out and put the LED in. Remember, if it doesn't work, flip it over. Now that it works, put it back together! Slide the clear cover in and put the opposite side in the roof first, making sure its covering the opening correctly, then push the other end up and snap the cover on.
Step 4: Before and After
These white LED's shouldn't ever need to be replaced, and are a lot brighter than the unsightly yellow bulbs.
Step 5: The End
Now that your done, admire your hard work and find what you need at night with plenty of light to help you!