Long time listener, first time caller. Taking one thing and making it into something new, and awesome, is fun. This is a project my fiancee and I took on last summer. We modded a Mac G5 that I got from a friend of mine, and turned it into a really great grill. If done right, like us, you can grill all summer, store it, and break it out the next summer and keep on grilling!
WHY a G5?
The G5 is made of anodized aluminum, which is the same material that most modern frying pans are made out of. Anodized aluminum has a very high melting point (thus more heat resistant) and as a byproduct of the anodization process it resists flaking. (http://www.anodizing.org/Anodizing/benefits.html)
Step 1: Things You Will Need (some You Need, Some Are Bells and Whistles)
Step 2: Gut the Insides Entirely...
Take off the side panel and gut the insides. You can search YouTube and find various videos on how to take out all the pieces. Essentially, tear everything out, take off all the small pieces attached to the inside, and cut off the small side bar that crosses the open area of the side of the tower. (This takes a little elbow grease, but if you happen to run out of that, just replace with some "get 'er done" or "Piece get out of my Mac!")
NB: Save the big metal plate that covers the power supply to cut and use later on.
Step 3: Drill Holes for the Grill/charcoal Racks
Drill holes appropriate to whatever bolt size you decide to use to hold the racks up, starting with the 2 holes already in the tower that are closest to the "bottom" of the grill. Because the G5 is made of anodized aluminum, the metal is pretty soft and easily drilled through.
Match the two bottom holes on the other side of the grill, and then you can either test the grill rack, or drill your second set of holes, approx. 3-inches higher than the lower holes.
We bought 2 grill racks, one of which fit perfectly, the other, we cut down to size.
Throw some bolts and nuts through the drilled holes, and test out with your grill racks.
Step 4: Attach the Grill
(1) Cut down the G5 removable side panel slightly to fit with the hinges.
(2) Attach hinges to the "top" of the grill, and then attach the side panel to the hinges as well.
(3) Cut the power supply plate so you have a small L-bracket type look, and attach that to the side panel by the hinges, on the surface that faces out (this will be used to brace the top of the grill when it is opened).
(4) We also put a couple of turn brackets on the top to lock the grill top in place when not in use ... drill holes, apply nuts and bolts.
(5) Bell #1, add a grill handle (bought ours at a grill supply store). ... drill hole, attach with included nuts and bolt.
(6) Bell #2, add grilling thermometer to side of grill by drilling a hole appropriate to the size of whatever thermometer you purchase. Grilling thermometers come with a way to hold the thermometer in place from the inside of the grill.
(7) Attach what is left of the power supply plate to the side of the grill that needs covering.
A mod we later added: We took off the side that was mostly open and instead used a piece of scrap metal from the G5 gutting with a couple of hinges as a door to allow access to slide the racks in and out from the side, and to allow additional air to enter while heating the coals.
Step 5: Grill!
Well, throw the grill up on a heat resistant surface (we used a small metal outdoor side table type thing), throw some coals in, and grill grill grill!
For full instruction, here is a video...