I think the one I drove was maybe earlier like 63 or so. It appeared to be a milk truck all its life without any piecing from anything else. I wasn't interested back then (1976) in the truck other than if it would get me back to the yard at the end of the route each day. Had a single hinged door in the back and a sliding door for access from the cab. I remember one time banging the carb with a rock as the float would sometimes stick and flood so I could get through the day.