I've never found a number stamped on my Fulton anywhere. Sorry I can't help with that. The only differences I've seen personally are the position of the upper foot of the end bracket and whether it has a center support (split windshield) or not. As to which number is which I'm no help at all. Good luck with your search.

Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.