you need to get a flywheel for your engine- the 305 in the IROC had a one piece rear seal engine with an externally balanced flywheel, you need one that is the same diameter (12 3/4") but for an older 2 piece seal engine. really common part, should be able to find one easily enough.
i hope you also have a place to get spare transmissions if you ever plan on doing more than just light throttle cruising with a T5- they weren't strong enough for GM to put them behind a 200hp 350 in the late 80's. the Mustang version of the World Class T5 is a little better, but not much...
what are you doing for a clutch linkage- the Camaro had a hydraulic setup.. and i think the way they tilted the T5 in the F body might cause clearance issues, too..
