Super A, Super A1, Super AI ????????????

I recently purchased an old yellow farmall state tractor used to load cinders for the highway department. (Either an "A", Super A, Super A1, Super AI.) The serial # is 331822. After where the "A" is marked, there is either a bottom half of a "1" or and "I". The symbol must of not completely stamped. The front axle is a round tube which I have been told does not make it an "I". But it also has about a 1.5" solid brace rod that supports the front axle which I have been told was only on the "I". I was wondering if anybody could help me figure out exactly what I have.

Thanks for any help!
Brian

Thanks,
Brian

I checked the engine serial number. It is FAAM 333437. It is about 1600 off from the chasis serial number. I know very little about the history of the tractor other than it was used by a hiway deartment in Southern Illinois. The tractor starts and runs very well and has a pipe frame loader on it.

Any other ideas on how to figure out what this is please let me know.

Thanks!!!,
Brian