Originally Posted by nasmovtx
I'm putting Caddy tail lights in my 37 Terraplane project. I useing 87-91 cadillac tail lights, and when I removed the light blubs, there was also a small, photo-cell looking device with 1 wire comming out of it. It has it's own hole, but I have no idea what it's for or how it works. Any one know more about this?? Thanks!
Take a close look at it it sounds a lot like the fiber optic for the "cats eye"
Take a flash light and try putting it close to the end that is inside the light housing, then look at the other end of the "wire" see if you see any light.
The "cats eye" is the set of red lights you see in the rear view mirror its mounted just above the rear window on the inside.
Instead of using wires and bulbs hey used fiber optic for the indicator lights on the front and rear.