Trying to set idle and due to dieing when in gear after it gets warm. Need help.

If the fuel level was too high it would stall with the rag placed over the carb.

Yeah, my error; been thread hopping, and got mixed up.

I reread the thread, and I know this has been mentioned before, but, boy-oh-boy it sure sounds like a vacuum leak, or a faulty low speed circuit.
I know slantys like to pull air in at the head to intake interface. And I know you said you checked, but...........
Normally I would suspect the brake booster, but I didn't see one in the video.
And like I said in an earlier post, too-tight valve lash can drop the vacuum as well.

But, here's an interesting thing; I don't recall ever having seen an engine continue to run with the carb completely covered by the rag. This leads me to think the vacuum leak is actually internal to the carb. This, cuz that's the only way the low speed circuit could continue to work. With no air flowing by the discharge port, neither would there be fuel, cuz it's the atmospheric air flowing by the port which causes the pressure drop, that alows air pressure in the float bowl to push fuel up the idle wells and out the ports................. Hey, is your bowl-vent set right? Some of those early 70s carbs had adjustable vents. They were to be closed with the engine off, and open at all other conditions. The electric throttle kicker made that happen. Check it out.