3-Way Light Switch Circuit Kit:

A 3-way electric light circuit is the convenient option for controlling the lights in the garage, over the sliding door, and by the back barn doors.

Mounted in the garage, it allows you to control the lighting from either inside the van or from the rear. When you return to the van in the dark, you can immediately light the garage and the interior of the sliding door, making it much easier to get organized and turn on other lights and fixtures.
Wiring diagram, 2 LED lights, 2 3-way switches and 10’ of awg wire.