paint between metal sheets, but an aluminum rivet in a drilled/punched hole has no paint insulator except under the head, if a good primer was used, and even that can be 'cut' by the setting ... welding is a different situation [the bumpers], just can't weld the 2 metals together
I'd never use the "usual" pop rivets where the mandrel pulls out and leaves a center hole, need quality bulb end blind rivets, and most rivet types are available as aluminum, steel, or stainless rivet, all with steel mandrels, but the bus originals are solid aluminum, set from both sides, no paint inside, no corrosion either
Bill
