I have a Fire Truck. I could give you the long version....BUT, the California Department of Forestry and Fire Protection (in those days it was know as the Division) purchased a '35 1 1/2 ton PU and added a Viking midship pump and the PTO off the 4 speed,a 300 gal water tank plus storage boxes in the bed that allowed 4 fire fighters to ride back there with fire fighting gear. It had one red light and siren.