Pennzoil was not in the business of making oil dispensers, they were in the oil business.
Somewhere on the unit should be an ID tag, that should tell you what company made it. Oil dispensers were made by at least 12 different companies.
After you determine the manuf. try and see if the ID tag has a model number, then go to my website:
www.petrocollect.comClick on literature then on the company, then on the model number, there should be a picture of the unit.
One more thing, the ID tag is usually on the pump, not on the tank.
Jack Sim