Inner fenders welded or bolted in?

Just as the title states, I'm wondering if the inner fender is welded, bolted or a combination of the two. I have my eyes on a 70 swinger that had the inner fenders pulled, found replacement fenders online with a quick search (so I know they can be found) and am wondering if they need to be welded in or if I can get away w/good ol' nuts and bolts.

Thanks in advance!