I'm looking to do exactly the same thing? I'm gonna post a thread later but heres what I've come up with!
So far we know I need a....
1. complete gn engine with all the intercooler piping, gn trans or a decent compatable high perf tranny(any recommendations) /wire harnees/ computer fuel lines and walbro 340 fuel pump, hotwire kit, a volt booster kit!
2. 9 bolt 3rd gen rear ( GTA's most not all and TTA had them) very strong and bolts right in be sure to get a disc brake posi unit with 3.27 or the 3.42 gears. along with the driveshaft . or a GN rear, but we might use a ford 9" rear w/ 3.93 gears...89 tta engine mounts, sphon crossmember and torque arm for a 89 tta
you will need to have a fuel tank from a fuel injected car . otherwise your asking for trouble.
a heater box and controls from a non ac car would make it all nice and clean.