Let see if this works:
Well, sort of. Ok, in this diagram the top right plug...goes to instrument cluster with gauges. I have a 72 C10 instrument cluster with oil pressure, temp gauges. My harness has 2 TAN wires in same pin location. On the schematic above, it does not show the 2 tan wires.
Also, the U shaped connector on the left...the purple wire, yellow, etc...all say "goes to directional hazard...." but I dont see where they actually go