Hello Hanno,
The funny thing is that the sketch with the measurement of 475 mm or (18-45/64") corresponds to the truck in the Australian museum with 10-50-16 tires... I'm inclined to say that this 16" (10 bolt) wheel might be at least 7" wide or so, given the information I have from Stuart... For some added perspective, my solid 16"x 8" wheels measure 446.8 mm or (17-9/16") and still accommodate a 9.50-16 tire... So the true size, or circumference must be the area in contact with the tire bead... Both would have to be the same. Anything outside of that area is obviously irrelevant and may differ from manufacturer to manufacturer... Does that make sense?
To touch on Andrew H. comment, I have the earlier truck, identical to a WA model, which I have seen with solid 16" wheels (IWM) and what seems to be 16" split wheels (laying in the dessert) but I may be mistaken. Maybe someone else can shed light into that mystery also...
Rest assured that if I could get my hands on a bunch of CMP wheels (or any suitable wartime wheel for a Chevrolet) I would cut them and re center them to fit the bolt circle and backspace of my truck... But there is nothing like that here in USA...
