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Well, If your asking me what I would do...(Muwa ha ha ha ha)
Seriously, I think a zero deck piston is a great start myself. KB has them with nice valve reliefs to handle some large lift cams.
Do the math and cc your heads for a final comp. ratio.
I myself would not go to big on valve size and just pocket port the head.
If I did not have an intake, I would do a RPM and a 750 cfm carb.
Cam would be a set above a RR cam. Which in itself (The RR cam) is very streetable and will provided good power and excellent street manors.
2-1/2 inch exhaust weather of manifolds or headers.
Stock Road Runners came with 335 HP engines, so a guess with a pocket porting and better intake....360 - 370 HP, excellent torque for this car for sure.