Recently purchased an '81 grand prix for $1500. Originally came with a 6 banger, but someone has stuck a 350 chevy in it. Butchered the wireing all to hell. Right now I am doing all the minor stuff I can. Any one no what I would need to change the transmission to a 700R4 and what kind of problems will I run into? Also what other GM vehicles can I pirate parts from such as disc brakes for the rear and maybe a posi rear end.