Dialing in a Carter AVS

I can’t answer the tune question outright. If the stock jet and rod have a .030 difference (100 jet .070 rod) then using a smaller primary carb with the same rod and jet would have it run rich because the smaller bore will have a higher velocity and pull more fuel.

This would also be true if you used the same carb and altered the rod & jet combo to .110 jet and a .080 rod. The reason being is there is more circumference even though the math would say both rod and jet have the same clearance between them.

Your best bet is an 02 sensor or take your time reading plugs and experiment.

Instead of searching for an old tuning kit, did you think to use an Edelbrock kit? If your AVS has the 3 step ride and high cover, you can switch to the AFB 2 step rods and the flat cover.