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

Good video
Do I see occasional puffs of smoke rising up out of the carb?
Is there any chance you set the valve lash too tight?

1) A too-tight valve lash, may not let the engine build enough compression to make the power required at low rpm to keep itself running, in gear. If you have solid lifters and you can't hear them clacking, chances are very good that the lash is too tight.
2) The rag over the carb seems to point to a vacuum leak. Often this will require a large curb-idle opening to provide the fuel to go with that air, to prevent a stall. This can then expose the vacuum advance port, which will then bring in some advance. All well n bad, but it idles with no load. Then when you put it into gear, the sudden drop in air-speed through the carb, drops the vacuum advance out, and then it stalls.
3) Another possibility is that the transfer ports are over-exposed due to a too-far-open throttle.They then can run dry at idle with the high vacuum, as the engine draws air around the blades through the t-ports.This condition is usually caused by insufficient idle-timing, but may also point to a vacuum leak.

Heres how I would attack this;
1) If I did see puffing out the carb, its time for a leak-down test. If for some reason, one or more intake valves are not seating closed during compression, it will be impossible to tune this beast.This is common on hi-mileage engines, as the valve spring pressure goes away, so you might as well check those if you take the valve cover off.
2) Lash the valves, Set the T-port sync., crank up the timing to get 550 rpm,and adjust the mixture screws with the engine running to best,smoothest,most stable,idle. Next go hunt for a vacuum leak. The slantys I've had, like to pull air in at the head. EGR valves can leak right through the diaphragms.Hunt.If you prove that there are no leaks, then;
3) prove your TDC timing mark, using a piston stop. Prove your centrifugal advance system is operating correctly;that is, smoothly up and down the rpm range, and no sticking.My slantys all liked plenty of idle-timing.
If you wish to leave the idle-timing up around 8* to 12*, you will have to limit your power-timing back to 32* to 36*

To set the T-port sync; pull the carb off, flip it upside down.With the throttle stopped against the speed screw, the transfer ports should appear as square to slightly rectangular.If you have A/C, that solenoid is a throttle-kicker. Make sure the throttle is properly parked.
Good luck.