Drivers side brake lights and signals not working

[Sicle]

Hi guys, I’m trying to get my 71 Suburban ready for the road, and have run into a snag. All my lights are working as they should except the drivers side rear signal and brake lights are not working. I’ve taken my tester to the wires at the rear tail light, and no power other than the parking lights, I don’t see any blown fuses and the flasher is working..... the only thing I can think of is the signal switch is faulty.....but the drivers side front signals work. Any ideas?

Thanks Brock