First of all, Chrysler takes un-used pigtails (ie: options, not used) and puts a single layer of tape around it (to rest of harness) so it can A) stay in place during assembly and B) be easily torn off if that pigtail is to be used during assembly.
A lot of times that tape comes off in 30-40 years or if other work is performed in that area.
These are from my '86 Fifth Ave - which I think might be helpful:
This is from the drivers seat looking up under the dash towards the L/F kick panel.
The gray/red wire goes to the parking brake (Right most circle).
The other red circle is for an optional under dash light, that turns on when door is open (...I think). At sometime in (my) cars life, I removed the bulb, and, um, forgot to put it back in . . . it appears. I think my Fifth might have two different under dash lights on it.
The blue arrow shows the connector is located behind the kick panel. I don't think this kick panel has been removed before. If a person could find a lamp like this one, your car could easily be upgraded.
This view is looking towards the front of the car and with the under-steering column plastic panel removed.
Hopefully this helps.
BudW