The only other simple solution is to tap into the wiring at the parking lights.
If you remove the switches and then remove the instrument cluster cover, you will have sufficient room to add a wire. Solder the splice, do not use crimp on termials or just wrap the wires around each other. Be sure to use heat shrink tubing to cover the wire splice. Electrical tape used by itself will come loose over time and cause problems. Electrical tape coated with liquid electrical tape from the hardware or home improvement stores is the only satisfactory way to use tape covered splices in automotive electrical work.
My personal choice would be to go to AutoZone and buy one of the Ford wiring pin kits. Then remove the switch, and remove the parking light pin from the plastic connector shell. Cut the pin off the wire, add your extra wire with the parking wire and crimp the two wires in the pin. Put the pin back in the plastic connector shell and put the connector on the switch and put the whole thing back it the dash.