[Fred T]

There are several ways to remove the rust, but without a proper finish, the bolts will rust even worse. Painting them is one way, but it doesn't work that well. Best if you plate them with cadmium, but that's not cheap. I would recommend using stainless steel bolts, which will eliminate the rusting problem. I don't recommend the hardware store variety, their strength is unknown. Got to one of the vendors and get them, and assemble with threadlocker. Keeps the threads sealed which prevents galling.