This 1964 Chevrolet Corvair pickup looks like a survivor from Detroit’s strangest experiment — original paint, original body, and the walk-through Rampside styling that made it an oddball when new. But its air-cooled flat-six is long gone, replaced by a 350 Chevy small block and an automatic that make it genuinely drivable today. It is for sale by the owner who built it. Watch to see how it runs.