Light bulb is missing. The question is, what kind or bulb?  There are no sockets, just the two
metal bars running the length of the car.  Bachmann calls it a light bar and still sells it. But,
what about the bulbs?  (No manual)

Passenger car light is not working.  Can someone explain how this works?  I don't see any bulbs, just two
metal bars running across the top of the car.  No bulbs or LEDs.  Just the lighting bar with leads to the trucks.
This is for the 85' Dome Passenger car.  Thanks