cam advice for 340 street motor

For stock late '72-73 pistons, yes. But he says he has L2316 Speed Pros and those should sit at the same height out of the block at the early ones, at around .018" above deck. (Compression height is 1.840".) I used 6 cc's in the eyebrows and now I see they are 7.5 cc's so that drops CR another 0.1 or so.

Just trying to provide some info to help answer the CR question. With the CR in the low-mid 9's range, then the cam can be bigger, and IMHO it is tweaking around the application to go 262 or 268 or thereabouts. But the 262 intake range is probably best with a lower stall TC in a general street cruiser. As in post #12, you're trading low RPM torque for high RPM HP, so it kinda depends now on what the OP wants to be doing with the car: Street cruise? Drag Race? Road race?

Getting the lift up is a worthwhile goal IMHO, and that points to maybe 1.6 rockers if that can be afforded (since the OP asked about rockers...). Another can o' worms; if one goes that route, then valvetrain stresses go up somewhat. (As Crackedback recently stated, it is easy to spend other people's $$ LOL)