Cluster fun.

[73 Duster 360]

I think I figured it out. The two black wires in the picture were once one wire. The guy who owned this car before me cut the wire as it entered the connector that bridges the front of the car to the back of the car. He did the same thing with the fuel sending unit wire in a failed attempt to install an aftermarket gauge.

I had the kick panel out because I accidentally thought I was missing a connector in my headlight clip. (See above posts)

Then I remembered the fuel gauge issue and how I saw two black wires that didn't seem to go anywhere and both just read as ground when I used my volt meter back when I was dealing with that whole issue. I realized it might have read ground because the switch was off.

So I found those "two" wires again and decided screw it and clipped a wire from one end to the other and sure enough my tail lights work!

I have to get the cluster back in place before I'll know if my instrument lights work but the fact that my tail lights didn't work and now they do is promising.

 

[67Dart273]

Missing connector. It is supposed to be, here is why

That terminal on the switch was the "older model" parking light power. That terminal of the switch is only hot in the park/ tail position, and cuts off park light power in "headlight" position.

All "Ma" did on the newer cars was to power BOTH park and tail off the "tail" switch contact--so the park lights stay on either "head" or "park" postions.

 

[73 Duster 360]

Missing connector. It is supposed to be, here is why

That terminal on the switch was the "older model" parking light power. That terminal of the switch is only hot in the park/ tail position, and cuts off park light power in "headlight" position.

All "Ma" did on the newer cars was to power BOTH park and tail off the "tail" switch contact--so the park lights stay on either "head" or "park" postions.

Interesting. I was wondering why there are 7 terminals and only 6 wires.

 

[Mattax]

I have to get the cluster back in place before I'll know if my instrument lights work

You could do a continuity or reistance check from the terminal to the ground for those lights.
Just be careful with the probe or alligator clip on the pin. In factjust touch the base so not to put side pressure on it.

You can also do one from the fuse holder to the round connector that plugs into the circuit board.

If the problem is with the socket holders you'll need to modify or get some used ones in good condition.
On my '85 GW I had to remove the contacts from the original (blue) and transplant them to the new holder.

This required surgery as the original contacts are held in with barbs.
And the new holder's contact openning was a little narrow.

Compared to old Wagoneers, mopars are plentiful and shouldn't have to go through all that unless you're in a jamb.