[lukecp]

I have had the same problem on my '72 before. Once, i was driving along after dark, on a moonless night, and the whole truck just died. Motor stopped, no lights worked, nothing electric. I had to feel around and find my flashlight. Turned out that the wire that goes off the + battery cable, the 10ga lead, had fallen out of its connecter. The connecter was the little black box (about 1"x1") that is mounted on the passenger side fender, next to the battery. If you loose a connection there, everything will go dead because all the power in the truck goes through that point. I would check all the connections on that wire, and trace it all the way up to the alternator. Also, check for a bad ground somewhere. Bad grounds have been known to do some pretty weird stuff.