how to achieve 600 to 650 hp sb 408?

We built a 416 a year or so ago, with the Comp XR286R, CNC ported Eddy RPM heads, 1.6 rockers, SV intake, 950 carb, 9.7 to 1 compression. It made 575hp 550tq.

I believe this same combo, with a little more compession and a Voodoo 60434 cam would have made 600+hp.