Tuning a Proform/Holley carb, what parts and tools?

This is the set of 80-61 drill bits I bought:
McMaster-Carr
This will cover the holes smaller than your standard numbered drill set.
61 is .0390" diameter, IFR's and e-holes will be smaller than that.
75 is .0210" diameter, and that's normally smaller than anything I can think of, maybe if your using 3 emulsion holes instead of 2.

Usually its best to hold the drill bit still and put the set screw in the drill chuck.
But this pin vise can be held in the drill chuck as well.
McMaster-Carr
I might have bought at least one of mine from ENCO or MSC Direct.
McMaster-Carr is convenient and fast, not always cheap.
ENCO has a lot of overseas stuff, but they also are more focused on tools for the machinest.

If you're just using the bits to measure diameter, then you can skip the pin vise.

Model railroaders and such are another user group for tiny drills, so if there is a hobby shop near you, they might carry them.

Your Proform main body and blocks will likely already have some things tapped and a selection of restrictors can be purchased. But if not, below is a thread on tapping and installing drilled set screws. any of the industrial supply places above (or locally) will have the tapps. I can't recall whether I bought mine locally, or from McMaster or Enco. The set screws almost certainly came from McMasters.
http://racingfuelsystems.myfunforum.org/viewtopic.php?f=25&t=121