Farmall Cub

Very very strange indeed. Actually your post helps me a bit. The s/n 54-Uxxxx denotes a type 54A blade then? I ask because I got this off of a Low-boy. Perhaps I've got the L-54 which would be a direct S/N sister to yours?????

Weird.

I think it's just an identification # as my 100 blade has 100 U 1111 on it also.