Magnum Rocker Help

Just beware of using factory small block Chevy rockers- they're 1.5:1 ratio, the Magnums are 1.6. You'll lose performance with the Chevy parts (big surprise!) unless you score some aftermarket 1.6 or better rockers.
I have read instances of SB Ford rockers also being used (1.6) but have never done so myself.