Firstfives.org

not lighting up. If it's not the bulb is it the Mylar? Plastic sheet connector That the bulb sits on that breaks down and won't carry current?

I've had problems with the copper film on the mylar oxidizing and needing to be cleaned with a pencil eraser for a good connection, but not the mylar itself. Kind of a funky arrangement until you consider the missing pixel problem on much later cars.

If it's not lighting up, it *may* be the case that your exterior bulb is out. Check to be sure. If that's not it, I don't know.

KenB