Classic/Antique Car Repair: Head light switch -56 ford F-100, ford f 100, side marker

Question
Pull the switch to the first notch, the parking lights come on. Pull the switch to the 2nd notch, the headlights come on, but the parking lights go off.  Both sets of lights seem to be working.  The brights are working fine but are the parking lights suppose to go off when headlights are turned on?

Answer
Yes, this is exactly what it is supposed to do.  The parking lights stay on only after 1968, when the Feds mandated side marker lights (the marker lights are wired to the parking light circuit).  This was the case for cars - I'm not a truck expert, buy my 65 Ford Pickup is still this way, and I doubt they would have made the change before 1968, at least, even though it probably wasn't a requirement for trucks until even later.  They stayed on in my 76 Chevy Pickup, so somewhere in there was the change.  If you want yours to stay on, you can move the parking light wire on the headlight switch over to the tail light terminal - then it will be like a later model truck.

Dick