[BB427]

The last street 460 I had was .030 over (466) with eagle H beam rods and a set of TRW L2443 forged pistons. They have a very slight tapered dome that does not effect flame travel. In a 72cc head they are around 12-1 depending on gasket thickness and deck height. I have also buit a std. bore 460 and used these same pistons but I milled the dome off for less comp. They are inexpensive pistons and work well in a street engine. I do not care for them in a race engine because of their weight. As far as cranking pressure goes you better have some. A cam with alot of overlap wont like that heavy car and an automatic trans. Put the lift to it and keep the duration down. You could actually drop the compression a little and have a cam ground that builds cyl. pressure and fool the motor into thinking it has more compression. Put a good gear reduction starter on it and go.
You don't need alot of HP you need frame twisting,doors out of adjustment,broken motor mounts torque.

Just an opinion
Good luck