I checked my other pinzgauer and it also shows signs of melted connectors at the brake switch. And seems to behave like my other showing 24 volts +
To install my Turbo diesel tail lights I undid the orange prong with two wires in it. I undid the black out light (pink) from the light switch and jumpered it to the two orange I removed from the hazard flasher. the only thing I can think of the melting could be from is to much current? but 4X21watts for brake dosnt seem that bad.

My brake lights work as does turn and tails light but that damn connector is getting HOT. Its odd that the switch shows 24+ till I connect it to my jumper to the pink black out wire that runs to my tail lights when I connect it being that it shows + I would think the tails lights would come on.
http://shup.com/Shup/376081/11063135517.png