Pivoting from 340 to 360

I'd just run a flat top piston and let the compression fall where it may. Prob will be a measured 9.5:1 or so. Don't waste time trying to build for quench or using the deflector/quench pad pistons with a cast iron head and no blueprinting. Keep the camshaft in the area you listed. I'd use a Comp but that's me. Get springs to match the camshaft - and be aware a lot of the purported .904 lifter designs need true dual springs so the spring seats and guides will need attention on the heads. (one of the big reasons I'd steer clear of them - you don't need it and you won't feel any difference) I agree - stock stamped rockers are fine assuming the camshaft can work with them (doesn't run lifters that needs adjustable valve train).