Stang wagon

That's the third mustang wagon custom I've seen pictures of, not to mention two concept vehicles. (although one of those may not have been functional)

The ford concept that never saw the light of day:

OMG! The assend of that last one looks like a Gremlin.

Back in the late 60s/early 70s there was a company which produced fiberglass kits to do those kinds of mods to Mustangs and Corvettes. I believe, not surprisingly, that JC Whitney carried at least some of them. The Corvette stationwagon kit was the one I recall best. Like a camper shell for an El Camino, it took the roof line back to the rear of the body, with either a lift up window or the whole thing lifted up. Can't recall which. Lot of people got into fiberglass stuff about the time of the VW dune buggy kits. Some got pretty wild. And people have continued to do so to the present.