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Even though the oldest PO didn't know who he got the car from, did he recall where/when?
It's worth searching old MA and NH newspaper ads to see if anything jives, long shot but there's lots of L78 ads in this thread you can try cruising first...
https://www.yenko.net/forum/showthre...135780&page=30
If you haven't yet, there's a New England Dragstrip group on F'Book you can try @ this link...
https://m.facebook.com/groups/240847...AFX46cl6Qb1a5o
Was your family dealership in Franklin 32-619 Sherman Chevrolet or something else?
Best of luck w/ your quest!
~ Pete
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