[Bill Hanlon]

I looked at the wiring diagram and do not see "circuits on fuses 3 (tail lights) and 9 (courtesy/dome/stop lamps) seem to meet somewhere". But I did notice that the turn signal switch is not seen in the wiring diagram.

Question for Larry: Were turn signals optional in '55 Pontiacs?

I've followed the wiring diagram circuits for fuse 3 (red) and fuse 9 (green), but cannot find anywhere they meet'

The missing turn signal switch would need to be inserted into the brake light circuit within the purple circle at the bottom of the wiring diagram,