Thermoquad idling issues

what's your idle-timing?
I have a Hughes cam; 230/237/110 @.050 tappet, with a lil more lift than the Comp. I can idle my 367 down to 550 in gear (manual trans) and pulling, with just 5*advance. On a good day, I can get her down to 500. The advertised on this cam is 276/286 @ .008 tappet. My normal idle-timing is ~12>14.

The point is, you'll get it figured out, just stick to it.
Make sure the metering rods are staying down at idle, altho, I don't think that is your problem.

I think I have the same mechanical fuel pump.
My secondaries are closed up tight.
I have a lil bypass air, thru the primaries, one hole in each throttle blade, I forget how big, but guessing ~3/32 (.094?) This was required to be able to sync the transfer slots to the mixture screws. Some TQs have an internal bypass, but you gotta go look for it, and IIRC it is not adjustable. It's been awhile since I looked at one.
Happy HotRodding