Finally got around to messing with the issue. The pin box has the collection of turn, running and hazard wires in a junction box fused off a 3 fuse bus bar.
The left hazard/brake/turn kept blowing as soon as I engaged it.
Took me a while but the problem was traced to the upper left turn/brake light (1157 bulb) assembly. The wiring was shorted somewhere between the fixture and the wall where it goes up from the frame.
There was NO WAY to feed a new wire so I was given an idea to run a new wire and hide it in the rear ramp spring channel.
It was a PITA and drilling at weird angles broke a few bits, but I got it licked.
Joe