Rough running

I recently had the original 350 in my 1989 9C1 rebuilt by a reputable shop. Now, I have the following problems:
1. The car usually won't start unless you put the accelerator to the floor, and I never had to touch it before. It has the original throttle-body injection setup and all emissions controls (I know from experience that in a fuel-injected car, the accelerator pedal never needs to be touched when starting).
2. The car will stall at every traffic light unless I keep constant pressure on the accelerator.
3. There is a constant smell of fuel while the car is running.

It's going back to the shop, but what could be causing this? Thanks.

WITH THE SMELL OF FUEL WHEN RUNNING best get this checked out quickly. I would say a fuel issue is the cause. could be sloppy wiring work after the rebuild in addition.

find the leaks and check for the fuel pressure and test proceedure. this will indicate if you have proper pressure and no leaks etc...

Sounds as if the injector pod may be leaking at its gasket, regulator or O ring seals, dumping raw fuel into the throttle body.

I never worked on the TBI, are the vacuum referenced fuel pressure? If so it would be a place to look for something disconnected.

The FPR on a TBI has no vacuum diaphragm - Just 11-13 PSIG under all conditions. The big injectors are sealed at the bottom of the pod with small cross-section O rings which are very easy to damage upon installation, even if they are oiled properly first.