[77 350 Shorty Wide]

Hi Dave,

First thing I would like to say is that this worked on "my" wiring harness it may not work on yours.

I started off by making sure the ground was good and I had the correct wire(s) for it. In tracing this, I discovered the LMC harness ground wire was blue with a white stripe. I then traced that back to their supplied connector the one that plugs into the old factory connector and I noticed it the LMC harness connector did not match up (pin position) with the factory connector. I did this be checking the schematic in my factory service manual. Once I matched up the ground circuit wires (pin) position correctly. It was a fifty fifty chance that the position of the two power wires would work.
My first test try was the same. High beams on when indicated switch to lows nothing. I swapped around the two power wires in the connector (pin positions) & voila worked the second time perfectly.

Basically they had it wired backwards.

Hope this helps. God Bless, Terry