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Let me tell you the story (as Indy Shah Safari McFly requested or suggested), as I remember it as the set prop master for all of the Back to the Future films.
Yes, the picture car was a 1946 Ford Convertible (made in America, after World War II). This was our car that Biff T-Boned into the manure truck (It really wasn't manure).
We had a second picture car, 1946-47 Ford hardtop from Mexico with kilometer and metric gages, that had been surgically altered by Kevin Pike and his superb effects department by removing the hardtop roof so it appeared to be an original 1946 Ford convertible. This car did the majority of the filming. It had mounts under the chassis to carry Marty on the skateboard, into and through the tunnel, and for Champion Co. crane shots. The mounts and cables were taken off later by George Lucas' Skywalker Ranch.
The real/original '46 Ford was the car that Biff T-Boned, along with his crew, into the manure truck in the Hill Valley Town Square. Dangerous BoB might be the only one who knows what became of that car and how it was brought back to life and by whom. "Has to do with his Craftsman's Union that he was a member of for 26+ years." Check back here in the near future for that story!
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