OK, the snow is melting, so here are the dimensions of the Braun light pods.
The base is 19” across, the top 16” across. They are 8 ½” tall. The base is 1” deep, the top is 3 ½” deep (to account for the angle of the sides, which I believe is the same on the vans as it is on my slant-side box unit – if the red light is not straight, adjust the angle of the whole pod accordingly).
The red lights have an additional 1” depth, and the white flood lights are flush at the base and 2” deep at the top (to angle them down).
See the pictures if they help. Good building, Greg!