I had a worn out aftermarket switch. It worked poorly. The switch plate on the harness was too thick. I bought a switch plate from Tyree Harris 804-556-5200, and a new, not-so-cheap light switch from one of the vendors that is made to exact specs of the Ford drawings. Be sure to get the matching bale. I still have the old harness wires, but all new switch and switch plate.
The switch plates are supposed to be .310-.315??? long term memory. Lots of harnesses with a too thick switch plate and repo cheap switches got out there. You can file the too thick switch plate and struggle or get the good stuff. I was frustrated and driving at night too.
Good luck