The six pack intake is probably the best factory intake to use for that type of build. Should be a fun combo.

The 500 rwhp is going to be tough to hit though. An easier target to hit would be 500 ft-lbs of torque. My low deck 470 with the AVS carb, RPM intake, Eddy heads and HP manifolds would lay down 530 ft-lbs of torque at 4300 rpm.