Tim, the last link I gave shows the load chart for 1950, and as I said, it shows both 15 and 16" for the 3100 at 4200#GVW - obviously either 15 or 16" would be available "stock", ie: from the factory when they attached the GVW tag, not 'special order' or aftermarket, what was "standard" is speculative and would no doubt depend on the particular plant/dealer/area .... asking "what was the configuration of a year" can not be answered other than by reference to the manuals and evidence on the specific truck asked about, such as the GVW tag - or by the original purchaser
Bill
