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Here's Yenko's 09/68 Pittsburg Press Ad as posted a few years back in the Old Newspaper thread w/ 15x 68's available including 2xM40 cars, one 325 + one 425 HP also both listed as having 140 Speedos.
Whether ad mistake or 140 Speedos added by Yenko, I think Joe's exactly right and any '68 M40 Yenko would've been a factory Auto car w/ engine swap, not trans conversion thus no 9737 M40 Yenkos.
~ Pete
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