My 68 6-banger has what I believe is a Holley 1940 carb, although it is stamped AUTOLITE. I understand the factory carb for this would have been an Autolite 1100 single barrell. Based on you guy's experience, should I replace the carb with a Autolite 1100 or try another brand of carb. I rebuilt this one but still have a stall problem when I floor it.

 

That just sounds like it gets too much gas or not enough and the engine dies. I replaced my 1v with a H/W 2v carb. Runs better and gas mileage is better.

 

Autolite one barrels have problems, so I would replace it with a 2 barrel or one barrel webber carb.

 

i think you need some kind of an adapter if you use a 2barrell. BA Mustang, can you direct hiom to your post?
there was some info in there
if you don't want to change your carb, the first things I'd try to do
a) look down the carb without aircleaner and engine off
push the throttle fully, you should see a stream of gas being pumped into the venturi
if not then that might be your problem
b) check for vacuum leaks
with engine in idle spray some wd40 around the carb, intake manifold, power booster (if you have one) etc
Do not spray right into carb.
if idle changes once you do that you might have a vacuum leak there