Post a picture of the dash and the engine. If the radiator is a Harrison it will have a date code on the upper tank. Why do you think this is a UPS truck? Is theIr brown paint visible? You may want to contact these vendors for additional information, provide them with a picture.
STEP VAN PARTS MORE STEP VAN PARTS Found this one on craigslist.
1961 GMC UPS PACKAGE CAR It is supposed to be an old UPS truck too. Contact him and see if he has additional info on the truck, manufacturer, vin plate location or any other identification. Notice that he is calling it a GMC!
