I did something close for a customer with a 65 Belvedere.
493 Hemi,4.350x4.150, 11to1 Compressiion,Stage V heads and rockers,MP crossram with original 770 Holleys and a 262 @ .050 solid roller for a street/strip car on pump gas it made 710hp @ 6500,torque curve was 580 @ 3000 to a peak of 632 @ 4700 and still has 580 @ 6500. Spring pressure is 200 on the seat and 600 over the nose with a Crower lifter with the axle and pushrod oiling.