66 Valiant - stranded on road trip

It's not clear to me exactly where this fuse is. If it's in the main battery/ alternator charging path, 30A IS NOT ENOUGH.

Also, fuse holder quality, uh, "varies." Putting a 30A fuse in a plastic automotive everyday replacement fuse holder is probably not going to hold up.

Part of problems like this are either connections RIGHT AT the fuse or nearby, which cause heating. that is, the "looser" and "more corroded" (can also be due to poor contact plating choices, IE radio shi$, these poor connections directly cause heat---the heat transfers to the fuse, which blows because it is running hotter.

ALSO installing an inline fuse close to a hot engine (manifold, example) can de-rate the fuse right out of the chute because of high ambient heat.