Well, the accel pump wont have that much effect at idle. It only plays a role as you open the throttle. Its is kind of sounding like the points are off, maybe the little screw came loose enough to allow the gap/dwell to change, or betwwen a failing coil and possibly bad resistor could have fould them pre-maturely.
Best thing I can suggest at this point, even though its a pain in the butt and no body likes to back-tract, start fresh... Go back through and make sure wires are in the correct order as well as snap tightly into thier sockets at the cap and at the plugs. Recheck the point gap, bring the engine to TDC and check that the rotor lines up with the #1 plug wire under the cap.
Recheck all the screws on the carb body to make sure theyre tight (sometimes they become loose after a rebuild if no thread locker is used), as well as the carb to manifold bolts/studs.
Try to start it when you verify that all of the above checks out fine and see how it does. If it sounds good, warm it up all the way and set the carb and timing. 750+/- rpm and start with the timing between 5-7* btdc and see how it acts when driving it. If your setting carb with a vac gauge expect between 15-17" readings at idle and not the typical 17-21"
Hope you get it figured out, I know how frustrating it is. The carter 1bbl cant be too much different that the 2bbl so Ill help you the best I can through those issues as well
