setting carb with vacuum gauge

Adjust each screw watching the gauge until it doesn't increase anymore, then back it off 1Hg. It may very well increase the idle, but you can adjust that up or down to where you want it, as long as it doesn't drop your vacuum reading.

When I did mine today I ended up with 15Hg and about 900 rpm on the idle, any lower and my vacuum dropped which messes with my brake booster. Since you have other than stock cam yours will probably be similar.