<VV> Origin of "Bone-Stock"?

[William Hubbell]

The definition of the term "Bone-Stock" as it pertains to the automotive
collecting hobby, is, as I understand it , "an original, unmodified car".
However, I have been unable to determine the origins of this peculiar term.
As the President of the Stock Corvair Group I would be very interested in
the answer.  Do we have any experts out there who know?

 

Note: other uses of the term:

Bone Stock (food industry) - a broth made from bones

Bone Stock (medicine) - Original or unmolested bone (so, this might be where
we get the term for cars?)

 

Bill Hubbell