OVRTROD, I noticed another set of lights underneath your headlights. Are those stock or some aftermarket item?
On my era of truck, I've never seen them installed. But my '46 truck has plugs that are currently in the same location. I was told once that many trucks were converted to hwy dept. trucks and it could have had a blinker there. Only thing is there is no evidence of previous wiring or signals. Still a mystery.