Changing to a 4 wire blinker switch will require that you have separate bulb filaments for turn signals and brake lights on the rear. I have no idea if the colors for a 4 wire switch would match a 7 wire switch, but the two output wires on a 4-wire switch would activate the left and right signal lights. The other two wires would be input from power and flasher. Here's a wiring diagram for a 4-wire turn signal switch.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
