A friend of mine made a very good point about it costing another $10k to dress out the LS7 crate engine. Ignition system, wiring harness, ECU, accessory drive, & headers, not to mention the Corvette transmission and required mods to fit it in a 3rdgen.Why not go with an ls7? what are you going to run for a rear and trans?
If I swapped in the Motown 427 SBC, I'd use the Richmond 6-Speed and a Spohn/Moser 12-bolt like I'm planning on doing. That would be the best benefit of using the Motown 427 SBC, it would work with anything that would fit a 350 SBC 3rdgen.
So, this would be the list for a 427 SBC swap:
427 SBC Roller Cam, Aluminum Heads:
MSD Ignition Box:
K&N Open Element:
Hooker Super Comp Headers:
Pair of 3" Cats:
Pair of 3" Mufflers:
Set of Tips:
This would cost about $5k more than a built 334, but there is no way I can't consider it because it just brings so much to the table in terms of aftermarket support.