Found the problem. First everything checked out fine switch , circuit breaker, relays , the problem was there is a connector between the fan and fuse board located behind the cowling above the fan blower motor. I assume is was never fully pressed together and took 280000 miles to finally jiggle loose. When it first started going out and I would tap the cowling it must have been enough to complete the circuit and run. Then it finally loosened itself completely and no longer powered resistor or fan. Wish I would have worked from the fan back vs switch down.
That's one for the books and I now have spare relays and a fan motor
Donny