Classic/Antique Car Repair: 1967 dash lights, variable resistor, 1967 mustang

Question
i have a 1967 mustang that the dash lights don't work. i found a female wire connector hanging loose under the dash near the light switch. i put -12v to the wire and the dash light lit, but i can't find anywhere to connect it. can you help?
thanks for your time

Answer
Judging from what you ave told me it sounds like the dash light wire that connects to the headlight switch. The lead connects to the switch at the end of the switch that is closest to the dash when the switch is installed. About the only way to see it is to use a mirror. The dash light are controlled by the variable resistor that is turned by the light switch knob.
Brad