Just some follow-up on doors, I am reading a book (long out-of-print) on the union sit-down strikes of the late 30's. In it is discusses how Chevrolet in particular had almost all body stampings come out of two plants. These plants, Flint's Fisher One and Clevelend-Fisher (majority of Chevrolet) were the "Mother Plants" which shipped parts in "knock-down" form to the assembly plants. Typical stock on hand was one months production at the assembly plant. As with all high-volume stampings and the resulting wear rates for the dies it is easy to see how variability in all panel sizing was possible. The book is titled "The great GM sitdown of '37 The Many & the Few (published in 1947) by Henry Kraus. It is a very interesting look at life on the line and the production strategies of GM.
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