IMO, you should spend the $$$ for a set of those billet secondary metering plates that allow you to adjust your outboard carb jets. You really can't tune all 6 "holes" by changing only the center carb's main jets.

I had my old Six Pack plates modified years ago to enable changing jets, but the new parts from Promax / Quick Fuel / whomever are a better way to go.

And if somebody was smart, they'd make the IFR circuits adjustable, too (if they haven't already).