The air horn is 4.75" in diameter.
The 'Carter AFB' is on the body of the carb on the rear left (assuming the primaries (with choke plate) are front facing).
The 2632 and 42009 are on the brass tag which is affixed to one of the screws holding the top of the carb on. Needless to say I am not confident this is the original tag but it may be.
I can post pictures tomorrow if that will help.
Thanks for helping out, I am always amazed and how many variations of carbs are out there.