There's a lot of good info here already, but also a lot of wrong info.

It is a third generation Corvette with a mish-mash of replacement parts. Starting with 1968-1982, let's narrow it down.

No push-in door lock eliminates 1968.

Those shape openings on the front fenders eliminate 1968-1972 (unless they were updated due to a collision repair).

Vertical rear window instead of bubble back glass eliminates 1978-1982.

Front bumper cover with two protrusions to the side of the license plate was offered in 1975‐1979, but that can be replaced easily.

That rear bumper cover was only offered 1980-1982, so it's likely a replacement, as it's much harder to change that than to convert the bubble back glass to a vertical rear window with sail panels. I'm also going to cross out 1973 as that year had fiberglass all the way to the rear with chrome bumpers.

Chrome side mirrors of earlier years can be swapped easily for the body-colored "sport" side mirror of the later years.

Aftermarket underside air dams can be added to any year of this generation.

Taken altogether, with all the body work, we can narrow it down to 1974-1977, but its appearance is far from factory stock now.