470 build - Need some insight - 68 Dart

I think the cork in the system will be the Holley intake feeding 470 cubes. Since you have the cam & intake, why not just try it??
I agree with you regarding the intake. The gentleman I bought it from went with this intake for hood clearance, but he spent considerable money working on the intake flow. It has been extensively ported and port matched, but is still probably the cork in the system. I plan to run a 1" or 2" spacer to smooth out things in the plenum, so that should help a bit as well.