It's got a double element rear wing, its something Gr.5. Its not the Greenwood 'Vette, that J-F slipped into screenshots thread. The screen looks too upright and a pillars too thick, for that. I know, I'm fudging for time.
Now that definitely looks like a DeKon Chevy Monza that Al Holbert raced in the IMSA GT. If so oh my ....
It must be the Chevy Monza @KopiB, the shade of blue is so unique. I spend my time searching for a lot of Opels like the Manta B, Ascona, GT... That windscreen is so GM-ish, lol.