The entire bed of the truck was FILLED with parts from a few different trucks. Also some interesting things behind the seat. Here's a short list...
Two flat tires, 3 headlight buckets, original driveshaft, engine head, oil pan, sections of the exhaust, 4 door handles, distributor, door window, one brake drum, speedo cable, running board splash aprons, and more.
I think the former owner was going to use the parts in the truck, but they may be the originals.