While I don't claim to be able to recognize and identify a Corvette chassis and underpinnings, my
guess based upon the apparently stretched wheelbase, near vertical windshield and heavy steel production car chassis components, is that the car is a Cobrette. Produced by a company that sold a cobra-like body conversion for C3 (and later) Corvettes. The difficult to read tag which appears to be double stamped looks like it could say Cobrette if I squint and tilt my head just right.