Could it be THIS simple?

[82 GT]

Originally Posted by PKRWUD

The Holley #4779 series of 750 DP's only had one PV, and were jetted accordingly (most were 70/80). If your plugs are bright white, try increasing them to 82's, but don't go any higher than 84's.

I tried 82 in the rear and lost about 1/2 MPH but I'm not sure if that was due to raising temperatures or what.
WHat about going from 72 to 74's in the front? If jetting the rear gains little or nothing, does that mean increasing the primary will yield the same results?