Ever part that "identifies" an L88 can be duplicated on a small block car...Without the real numbers, or the original build sheet/window sticker/shipping invoice, it's gonna be extremely hard to authenticate.
The '68-9 L88s had heaters, by law. The '67s did not, tho.
Someone saying it is real just due to the installed equipment might be trying to pull a fast one, or, as Bruce says, might have been sold the same line when they bought it.
Kevin Mackay is the L88 guru...might try contacting him for more info/help in authenticating the car.
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