I also found this; Take the headlight switch out of the dash, just hanging down underneath. With an ice pic type test light and the switch in the off position, find the one hot terminal. This is the incoming hot lead ignore this terminal. Next, pull the headlight switch on to park position and find two new terminals that became hot. These two are the tail light and parking light terminals. Turn off the switch, and with two of these blue wire splices make jumper between the two with 14 or 16-gauge wire. With this done in park the two terminal are in parallel (no problem) when you pull the switch to headlights the tail light terminal will also feed the parking lights up front. From the ‘70s Ford wired the front and rear circuits together to the same terminal on the head lamp switch. Or, just swap one wire into another position on the headlight switch connector and you're done.