welcome to the shop hope, is it a 55 1st or 2nd?
the 55 2nd has a 6400 model with 16,000 GVW that has a 156.5" WB, called a 2 ton, and the vin would start with a W - the 109hp engine would be the usual 235, prolly the loadmaster version in a 6400
for info about pictures here, see the Manual linked below, we love pictures
Bill