Can't get the idle right

[JOES31]

I wonder if I can get some advice. I just rebuilt two Zenith carbs for the 31 Tudor. I can't get that sewing machine idle from either carb. Power is good, no backfiring or stuttering. Good throttle response. It idles but not as smooth as I think it should. I installed flow tested jets from Renners and the float is set properly. No leaks. The GAV is at 1/4 open and changing it doesn't smooth it out. The engine has about 400 miles since it was rebuilt but it sat for 15 years until 4 month ago when I started working on it. Timing is set according to Les Andrews videos and it has a new intake manifold, rotor cap, rotor, plugs, points and condenser. I set the points to .018. Can't find any vacuum leaks but I did not bush the throttle and there is a very small amount of play but I don't think it is enough to create a rough idle. The idle mixture screw doesn't seem to make much difference except it will stall like it should when fully closed. Is this the way Model A's idle or am I missing something?

Any ideas are appreciated.

Joe