Well it depends on your Transfer port sync, and whether or not the idle ports have to augment them.
If your Transfer slots are not supplying enough fuel at idle, then you have to increase the mixture screws to make it idle. Then when you tip in the throttles, maybe you get a a lil tip-in sag until the transfers wake up.
If your Transfers are supplying too much at idle, then you will need to lean out the mixture screws,for a nice idle . And again you get tip-in issues.
In N/P, the mixture screws can work even at 2000 rpm; just put the carb up on the fast idle cam, and find out