I'm sure this is asked once a day..........

[gonezo]

I'm sure this is asked once a day..........but(<--keyword). Ok, so I'm a little embarrassed to ask this because I've come to find this is asked alot but I have been scouring the board for at least a month and a half to figure this out. I have a '72 step and cannot get the rear lights to work. I've ran ground from the neg-batt terminal to the body and frame scouring under the connections and wire brushing the screws. I've done the same with straps between the frame and body all the way back. I have rewired from firewall harness to rear light harness, cleaned all connections and done continuity test on the rear taillight harness. Bought brand new bulbs. Swapped out all fuses with new fuses in the fuse box(everyone including ones that are not associated with the lights) have grounded the ground leg off the rear harness correctly. Replaced the dimmer switch although I think that only pertains to the headlights. I've checked continuity of the rear blinker assemblies.

I guess my real question is what else under the dash or in the column could be causing the rear lights not to work? I've looked the wire diagram up and down.

Would the gauge cluster have anything to do with it.

Any direction would be much appreciated.