I had a 57 Chev where i found assembly line check off cards under the head liner on both sides (left and right) of the headliner. The one side was mint and the other side was not. I still have them. My old 57 Chev was an American car and i found some old American coins under the rear seat from the late forties and early fifties. Cool finds for sure.
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1957 Pontiac Pathfinder Deluxe sedan restored 261 six
1974 Chevrolet Caprice Estate wagon low mileage original 400 V-8