I would feel safe to assume the COE could have been made by the same company. Body lines would be different because of different cabs. Also, in the '48 they used the quarter glass and frame from a '42-48 coupe. Mayby they used windows from a different vehicle. My friend also said they used the back panels from Mack trucks. When you look head on at the '48 it looks like the doors are half open. To make the cab wider they inserts triangluar pieces in the floor and roof so the back of the doors stick out:



I would like to see a front on shoot of the COE to see if they did the same.