452 heads on a 1965 Wedge ?

If your 65 motor has its original steel shim head gaskets, switching to Fel Pro .039 inch thick gaskets will lower the CR probably close to half a point.

But I doubt the original CR was actually 10.3 to one. If the motor is in the car now and running, I'd drive it and see how it does. My guess it you'll be OK.