I found a combination of problems.
1) The coolant port on the driver side of the head for the water choke is plugged, so the choke thermal spring never got hot.
2) Because of #1, the previous owner adjusted the choke to basically always open. Unfortunately I can't seem to unblock the coolant port.
3) The high idle choke screw was set IN so far that it was affecting warm idle... the carb was running on primary jets because the idle was so high.
Idle is down to 900-1000 rpms, running on the idle jets (now the mixture screw actually makes a change, and the engine dies if I unplug the idle solenoid.) It's not perfect, but getting closer. Will have to let it cool down and see what the cold start is like now.
Still not sure what the broken micro switch was for, or which model years had that?
Also, a clamp failed on the radiator hose and burn the crap out of my wrist. Hopefully it doesn't blister, but it's swollen, red, and it hurts
