Hey Dan

Your goals are easily achievable

-470 rotating assembly with 10:1 compression
-MP 452 aluminum heads or RPM's (The 452's will work with your existing headers which are fine at that power level)
-Comp XS282S solid flat tappet cam (nitrided)
-EDM oiling lifters
-Crane or Isky Ductile iron rockers/Chromemoly pushrods

*the rest looks fine

This combo should make 525hp/550tq all day long with a big fat torque curve, run on pump gas and have a nice lopey idle


Ron


Ps. Here is a dyno sheet on one I helped with : 448ci RB build with RPM heads (unported) using the XS282S Comp solid. Runs fine on pump gas, idles at 850rpm with a nice rumpity idle and will boil the tires at will !