Not sure what Idaho museum was hosting this wagon (see last paragraph of description).
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“Body has had the top cut off and the rear changed to add a rumble seat. Very well done . The fabrication that was done is excellent. Nice finish work. The body was then installed on a custom truck frame .Body work is nice and the paint is nice with real wood trim.. The rumble seat is easy to open and is very strong.
Drive train is a 350 chevy with a nice cam and hei ignition. All new aluminium radiator with new exhaust. Transmission is a turbo 350 that works fine. The rear end is a heavy duty truck rearend? Large tires are also nearly new.