I'm not sure if this is an appropriate place to ask this question, but does anyone know why a car would need two window regulators per door? I can't figure out which car this is, so I don't even know what to look for.
Some older cars have more than one controllable "window" on the door, so there needs to be more than one window crank. For example, here's a photo showing a car door with 2 window cranks. You can tell that there's 2 different pieces of the window that can be controlled.
One is the side glass regulator (long handle), the other (short handle) is the wing vent regulator.