If you are talking about the rivets at the top of the arch of the wheel opening, those are stock. They were not bolts.
The first time I took my resto-mod '49 to a local cruise in, a rough looking guy walked up to my truck and looked me in the eye and just stood there smiling. It seemed odd, so I asked him what was he smiling about. He simply pointed at the rivets in the fender and said, "That."
He was appreciative of the fact that I went to the trouble to make sure that those rivets were there. Most folks seem to just weld the inner brace to the fender and mud over it. He made me smile that day.
