Burdar I put in new flasher dealies for both turn signals and hazard. I can swap the two units and still I have turn signals
but no hazard. Right now the turn signals won't turn off after a turn, so I want to replace the turn switch anyway.
I haven't searched yet for that, I would prefer to find an NOS piece if possible but maybe they are now unobtanium.
Dan Stern (Daniel Stern Lighting Consultancy) had some but not sure if they are the correct ones for your truck.
He posts on FABO and Slant Six forums but you could just look up his website for contact info.
Looking at the full size pdf for the '79 truck,
The turn signal flasher gets power from the run circuit. J10A feeds the fuse. The fuse in turn feeds the flasher via the short connector (F11A)
Hazzard is fed from F38 (prple with white) which comes direct from the battery. So check that for power into the fuse. The hazzard fuse connects to the flasher via F40 (pink). Check that next.
