Mock up the valve train and check for pushrod clearance with those heads, especially with 3/8" pushrods. The issue is usually at the intake runners.

Also, they supposedly were having problems with the locks at some point with those heads. They now come with Comp 7* locks and I haven't heard anything negative recently. The retainers actually look ok to me. Also, check for rocker arm/retainer clearance.

FYI, We recently cc'd a set of Stealths and it came out to 82cc. They will all be slightly different, but that should get you close when calculating CR.