I'm not for sure, but I believe there is a different fender for a shortbed model and a longbed model. I got a fender from someone recently and he had a shortbed. It has the hole cut out of it in the part where the tire sits like your picture. But the original fender I had when I brought the truck home didn't have it, and I know it was the original as my grandparents bought it new in 64' and I'm the 2nd owner. It may not be the difeerence in fenders as much as where it is located due to the bed size.
Tramp
