Corvette Fever magazine is doing a project and is using a 5.3 in a 1987 Corvette. If I remember correctly, they used an LS1 aluminum flywheel and it bolted to the 5.3 crank with no problems. I believe GM offers a pilot bearing that installs in the outer bore of the crankshaft so if you use an old style small block/big block bellhousing, just about any type of transmission that was originally used behind a Gen1 or Gen2 engine will work. That includes Muncie, T10, T5 or T56 among others.

 

Mark, I used a GTO flywheel.