Assumptions:
4.32 x 3.75 bore and stroke
Deck height 10.725
comp height of piston 2.030
Rod length 6.768
Head gasket 5cc
Head volume 92cc

Calculated
901.1 cc swept volume
deck clearance 0.052
deck clearance volume 12.5cc
volume above piston 109.5cc
compression ratio 9.229:1

Change head volume to 88cc
New CR is 9.54:1

This explains why my uncle could brag about running his high compression Plymouths on regular gas.

Buy a regular gasket set and add the composition head gasket and you're looking at 8.9:1 or thereabouts.

R.