Do you also Have a Set of the camel hump Fuelly Heads Like you Talked about in the First Post ? The #3876775 Heads have Small 1.72 in Valves . Also at Best with Thin .015" Head gaskets 75cc Chambers and Flat top pistons . you will have 8.75.1 C/R . That C/R is ok but the 1.72 in Valves will really cut down your HP . This Corvette sound Like it's not a #-matching Car . Are you just Looking to make it a Hot Rod ? And what Kind of Budget are you on ? You may be best to buy a New set of Heads . I think the World S/R Torquer heads with the 67cc Chambers 1.94in / 1.50 ex Valves would be the ones for your Car . They also make them with 2.02 in / 1.60 ex Valves . But with that powerglide trans you will not want to kill your bottom end torque . If you have Fuelly Heads that are in Good shape Run Them .