However, I've discovered that the dimmer switch wiring had to be wired to the center pole (power in) and one of the terminals at the dimmer along with the instrument panel indicator light for the High Beam.
I would double check your wiring on the dimmer switch. I happened to change mine out today and had it wired incorrectly (power in was on the center terminal, so had no high beams.) But the switch was intermittent high resistance anyway, so I put in a NOS dimmer switch. Both were marked with "BAT." on the upper terminal. (See pic.)
As far as the high beam indicator light, that's shown connected to the fuse box for high beam, so there are just a single wires terminated at the dimmer switch, (battery feed, high and low.)
I also replaced my headlight switch, as it was a bit high resistance also, and discovered that the mounting nut was chrome plated plastic, which promptly stripped it's threads. This replacement switch was the same style as the one in the truck when I got it, but it at least had a pot metal nut (which I reused.) The knob that screws on the shaft was also chromed plastic. Replacement are getting cheaper (read that as crappier) by the day.
