OK. Carb was rebuilt and is running great. Apparently, the guy in the shop is the Charlie Daniels of the carb -- a wizard. Picked up my car at 3:30 PM yesterday and man was it great to have it back. Runs better than it has in 4 years. One of the members here wrote me this in an email:
Quadrajet carburetors are subject to leakage/seepage around lead plugs found at the base of the jet wells. These plugs are visible from the bottom of the carburetor. When they’re over the hill and begin to leak, they allow gasoline to drain out of the bowl and into the intake manifold. They will do it every time the car is shut off and that dumps at least 1/3 of a cup of raw gasoline that has to evaporate or be expelled from the cylinders upon restart. Plus, before the car can run again, the bowl has to refill with gasoline, a process that requires spinning over the motor with the starter unless you have an electric fuel pump. It sounds as if the lead plugs are doing a little more than seeping in your carburetor. They are probably dripping rather than seeping.
I think this is spot-on as to what was happening. The mech rebuilt the carb, tuned it, and voila, car runs great. I'm happy.