Make sure the secondaries aren't hanging a bit off of the idle position;

Make sure that you spray a bit of a non drying lubricant, like CRC on the
choke mechanism and secondary mechanisms.

Make sure that when you turn off the motor, even though the choke doesn't
close all the way, the bi-metal electrically heated spring. When cooling
doesn't allow the fast idle cam to go one step fast, then never heats up
enough to pull it back to the lowest point again.

If the electric choke cover is bolted, you can go one or two lines towards
the colder setting(counter clockwise) if riveted, you'll have to buy
replacement rivets and drill out the old ones, then rotate the choke coil a
bit towards colder. As mentioned before.

If the cover is keyed: File the f.cking thing after doing this. Set your
idle, when the choke opens totally, look at the fast idle cam, behind the
choke stove after accelerating the car once or twice. no need to punch it,
just moderately accelerate it to release the choke.

See if the screw is on the lowest step on the cam, this may be why you can't
get the car to idle?

I hope this helps?

Refinish King