I've wondered this myself. I'd be interested in seeing if it's still out there. I have the same truck that needs a paint job. The thought has crossed my mind more than once.
I was just playing with my HD DVD of it. It looks like a '77 F-250 Ranger. It was stock suspension with a 3" body lift and had a Ramsey winch mounted on the front bumper. It had clearance lights on the top of the cab. The rear bumper was a chrome step bumper with polished diamond plate mounted to cover the gap in the back left by the body lift. Looks like around 33" tires on it. The rollbar was fabbed. I've never seen one like it before or since that truck. It had two round 8" Hyliters on it and two rectangle lights mounted outside of those. It had three chrome tie down "T" hooks down each side of the bed. It even had the same wheels as my truck. It would be a cool ride, but I'm missing alot of expensive trim since my truck is only an F-150 Custom.
Thanks for the picture! See? I was right about most of the stuff. It only got a few seconds of air time in the movie and none of them were very good shots. It's amazing how many people (like me) knew the name instantly and recognize the truck from that.
I saw a replica of it at a car show about two years ago in South Georgia. The rims were different, and it didn't have a body lift at all, but otherwise it was pretty dead on. I never got to talk to the owner.