[Ed Wright]

Richie is correct. Vacuum leaks cause lean issues.
Throttle blades open too far allow fuel to be pulled from the boosters. Will cause very rich conditions. 1/4" float level should be fine. If you have not drilled the primary throttle blades, you likely have the idle speed screw run in too far, opening the throttle blades too far. Pull it, flip it over, the throttle blades should not be above the idle fuel slots in the base plate. Drilling air holes in the throttle blades is always needed with much of a cam, to prevent having to open the throttle blades far enough to pull fuel from the boosters.
Just look down in the primaries with it idling. Top of the throttle blades should be dry, with nothing coming out of the boosters.
Good luck.