63 Dart Mystery Circuit Board Washer

I should mention, the cigarette lighter has never been connected in the time I've owned the car so I wrote that off right away. I considered the back of the speedo but there's no way for it to go on without clearly preventing a proper connection so my best guess is it was underneath where the cluster of wires connects to the circuit board above and between the ignition and cigarette lighter.

Again, suuuper green on the electronics so I didn't want to just pop it in and see for fear of frying something.