I've driven trucks like this. 3/4 ton with the 6. Old, slow and beat up, they soldiered on into the early 2000's. Even now, I still see a few on the road, and more sitting forgotten in the side yards and back lots of farms and oil companies around town. In many ways this build represents the "Real American Truck". Purchased with no options and the baseline motor, thrashed from the first day, they worked & worked until they just flat wore out. These are the "Invisible Trucks".
Great Tribute, Chuck!