I agree with Truckernix. The full pressure 235 came in '53 PG equipped cars, and all '54 applications. Now, concerning the starter. Watch out for the number of teeth on the ring gear and the starter gear. They differ from 6 volt to 12 volt. In '54, Chevy still used 6 volt for everything. By '57, everything had been changed to 12 volt. Probably the easiest way to overcome this, is to use the '57 flywheel on the '54 engine.