Cool coil cover, no idea where they could find it. It sure breaks from the usual beer can trend
Well, a commentor cleared this mystery up, Tondeleo knew that "The STOP light is an old cop car light. It would be mounted on the front passenger side fender of the car, facing backwards at a 45 degree angle. As they would overtake the car they were pulling over, they would turn on the STOP sign."
I've also just recently seen them on the back of old school busses