Thermoquad........Ok AJ, WHAT NOW?

The T slot adjustment on the TQ is no different than any other carb. Ideally, you want 020 to 040 of slot at idle [ in gear if auto ].
Many of these carbs had bypass air holes in the baseplate [ BP ], near the mixture screws. The holes are drilled such that air enters from the t/bore along a slot in the top of the BP, through the holes & exits under the BP below the t/blades. If insufficient T slot is showing, these holes can be plugged which might be enough to get the desired t slot position, &/or smaller holes drilled.
About 25* of idle timing would be good for your combo.

Lack of vacuum at rear of carb. Looking at the rear of the carb, the nipple closest to the AV dashpot connects to the dashpot & should have manifold vacuum; the nipple closest to the centre of the carb has manifold vacuum.
So, no vac at the AV dashpot nipple? Two possible reasons. Some of these carbs use a brass nipple with a very small orifice, perhaps 0.015". It could be blocked, so poke with some wire.
To get vac on this nipple, the sec blades need to be fully closed at idle. The closed blade seals off a small hole in the BP. If the hole is not properly sealed because of improperly positioned t/blade, you will get no vac at the dashpot nipple.