Brake light issues

[Turbo4whl]

I ended up replacing the rear harness, the bulb sockets, all the rear ground wires, the blinker flasher, and I redid the connect of the white wire under the steering column that runs to the stop light switch and after all that, I finally have brake lights!

I read this post through twice. Seems like the original issue is the truck bed lost it's ground. Common on these old trucks. The bed gets it ground through the bolts to the frame. Rust ends up insulating the bed and no ground. Need to add a 12 gauge wire bolted from the bed to the frame.

When you replace all the light sockets, you may have added new problems. Are the light sockets aftermarket? Some aftermarket sockets are so cheap the bulbs do not fit and lock in correctly. Are they wired correctly as @Ricko1966 stated?

Is the new headlight switch correct?

 

[Fjordlander]

You probably have more than 1 problem.Headlight switch is wired wrong. It picks up power for the headlights from a fusible link.You probably also have a short in a headlight wire. Headlight switch picks up power for the taillights from the fuse. You need to grab a wiring schematic and look real hard at how you have things run in comparison to the schematic.

I replaced the harness going to the tail lights but I haven't checked the wiring to the headlights. I'll double check everything is still right and right with the taillights.
I'll look at the switch wiring too. I was hoping I wouldn't have to tackle that since it's all bundled with the rest of the harness but you're probably right. The PO really did a number on the wiring in this truck

 

[Fjordlander]

I read this post through twice. Seems like the original issue is the truck bed lost it's ground. Common on these old trucks. The bed gets it ground through the bolts to the frame. Rust ends up insulating the bed and no ground. Need to add a 12 gauge wire bolted from the bed to the frame.

When you replace all the light sockets, you may have added new problems. Are the light sockets aftermarket? Some aftermarket sockets are so cheap the bulbs do not fit and lock in correctly. Are they wired correctly as @Ricko1966 stated?

Is the new headlight switch correct?

I didn't know about the bed ground! I'll check that out.
The sockets are from AC Delco and they are wired the same as the sockets I removed. The bulbs seem to fit and lock well and all the tail lights are working now.
I'll check the wiring for the new headlight switch but the switch itself is correct. There could be a problem further back in the wiring harness.