Here's my Stepside step bumper. It was on the truck when I bought it in June of 1973.
Most likely it was a dealer extra. Truck was originally sold by Felix Chevrolet in LA. There was a manufacturer tag from Saf-T-Bumper in Los Angeles.
I like it. It's solid. It's taken a lot of abuse and been straightened out. Good footing w/o dropping the tailgate. Even been used as an anvil on occasion.
''Kids'' can have their roll pans -- I still need a Truck.
