GRRRR!!!! 68 C10 Electrical problems again!!

[HIGHWAY BY THE SEA]

This weekend when I was on my trip to Georgia to visit Maddkidd007 and pick up my wheels, my wife borrowed my 68 stepside (the ONLY time I have ever allowed her to drive it). It inexplicably lost all power while she was driving it, so upon my return home today I checked under the hood. The battery has a FULL charge, and I can find no popped fuses in the fusible links either. Even the headlights do not work!! ARRRGGGHH!!!!!
Then she borrowed my 81 C10 stepside and it did EXACTLY the same thing (after it was parked). I have not had a chance to go see it at her work place yet so I am just as clueless. Double ARRRGGHHHH!!!