How to properly drill carb jets?

Somehow missed your thread when it mattered, but I have that same carb that I was using on my 410, had the same deal as you. You mention primary jets sized from 76-82 That is the kit for the 625 carb. You need the kit for the 750 which comes with 87/89/91 primaries, as well as 54-38, 56-40, and 58-44 rods. What rod were you running with the 82's?