[Hanno Spoelstra]

Jordan Baker shared an amazing (to me) find - a nice tidbit of info on the "Application of blackout to conventional pattern vehicles (Passenger Cars and Trucks":

Part of the blackout lighting kit for Chevy cars in Canadian use. The white rubber part was mounted under the back end of the car for the rear diff light to shine on. The black item is a bracket for holding all of the lighting switches.
$100 Cnd plus shipping.
Send me a msg if interested.