I need to find out if a C-5 T-56 can fit into an 88 GTA. I would be buying the transmission only Ill need flywheel, bellhousing, and other misc stuff. Can probably get trans for $250-$300. Is that a good deal? This would be used in changing from auto to manual trans.

I believe the tailshaft is a different lenth and a different spline. From what I have heard corvette t56's dont fit in an fbody period.

The T-56 in a C5 bolts to the rear end, and has a torque tube that runs up to the motor.

So no, I kinda doubt it'll be a bolt-in, or even very close; athough with enough acetylene, almost anything is eventually possible.