Slant six performance parts

No track but would like to get more pep for daily driving for the 6 months a year I drive it.
Plan to miil heads and go to 2 1/2" dual exhaust. Just wondering if I should go with a two or four barrel intake/carb set-up. I've read a 4 barrel is to much unless your dragging. Do I need to change to a 8 3/4 end..I've read different points of view on this.

I'm looking at the Super Six set-up...what kind of HP can I expect with this type of set-up?