Update: Part II
Well, I've concluded it definitely has something to do with the logic board, and heat. I've installed G4FanControl, and by keeping the fans pretty much constantly running, and having the back end propped up leaving a few inches of space between the computer and the surface, I am able to keep it in working order. Also, the AirPort issue has somehow resolved itself after I found the original card it came with after misplacing it for a while, and put it back in. Works like a charm, go figure.
It's a shame I don't have more knowledge in soldering and what have you, I could make this a perfectly good machine. But, I do have one of those combination laptop stands/cooling fan (...somewhere) which should alleviate some of the workload on the internal fan.
In the end, I'm just glad after 8 months of tinkering and researching, it finally WORKS. KIND OF.
Thanks for all your help, MR members! Couldn't have done it without y'all.
