Used to see a Pl-12 as I drove past Ardmore, and boggled everytime, but I have never seen its predecessor, the Bennett Airtruck (with a c), which looks as though it was cobbled together from miscellaneous parts (which, I believe, it was).
When I was looking up the PL-12 in Wikipedia, I had a senior moment with the manufacturer's name, and entered "Panavia Airtruk." There's a thought.