Carter AFB - 1966 273 4bbl 4-speed M/T

I do have a 1966 Barracuda 4-speed manual with the HiPo Engine and the 4bbl carburetor (no CAP)

This carb. has the tag#4120 and belonged to a automatic transmission-assembly (A/T) from wich I took it off. It's rebuilt.

--> Correct would be a Carter AFB with tag#4119 for manual transmission (M/T). (...If I only had one... :rolleyes:)

Does anyone know the difference of M/T and A/T?

It doesn't take full throttle (f.e. in 2nd gear). If I push the pedal slowly, there is no problem.
Before checking ignition and more, I am trying to figure out the difference in carbs.

Thanks, Robert