66 cuda electrical

Since you have headlights and the brake warning lights up, that indicates the switch is getting power and SOMETHING is working.

This is troubling as I would think that if the warning light comes on, you'd have other power.

What do you have for a shop manual/ wiring diagram? The problem with the 66 Ply manual over at MyMopar is that it does not have the special wiring for the Cuda Rally dash, and possibly other changes

You can get somewhat useful diagrams over there as well

Is this a stick or automatic?

Only 26K? wow