When cold, my Thermoquad equipped small block runs pig rich until warmed up, sometimes loading up so bad that it belches black smog and idle speed lowers significantly. The wells were just resealed, but when warm, it is still requires a little cranking and provides a smoke cloud. Runs smoother when warm, but fuel mileage is not that great. I am suspecting a maladjusted choke. When cold, the choke door only seems slightly cracked open. If the choke, what is the best way to adjust to get the door to open a bit more, or how can I help this out?

Check the choke pull-off and or adjust the pull-off link as necessary for cold run mixture, that’s its function. Adjustment procedure is spelled out in the FSM. That said, important to be sure carb is set-up correctly for operating temperature first.

Two things come to mind.
1. The heat crossover passage may be carboned solid.
This is pretty common on small blocks, at least to me. After starting it (cold) see how long the choke well takes to get hot.
2. If yours has it, the electric choke assist may not be working.

Both the above afflict my '85 D100, though the motor is out of something else, it is a 318/factory TQ. I suspect somewhere around '77-78 vintage car.
Also, if the butterfly in the right manifold is mia or stuck, this will make for slow choke action.

The poor running begins almost immediately after starting....no real time for heat to even be a factor. Starting is pretty easy.