I think there is a distinct difference between pre- and post-war trucks and your description of your '41 may typify that difference. Post-war a 1-ton is a big pickup. Pre-war its a lighter truck. I'm not sure exactly when the change occurred, but I've noticed a difference in the designations about the same time as WWII that seems to fit.
Now someone is going to point out that a 4100 and a 3800 share the same frame, making an AD 1-ton very similar to the shortest 1-1/2 trucks, but the 1-ton shares much more with the 3/4-ton including all the sheet metal forward of the bed and the same Eaton rear-end housing.
So if the early 1-ton Suburban was custom built and made of wood what would stop you from building one based on pictures? If I had any passion for them I'm sure I would be thinking about it.
