An unnamed muscle car is due to appear in Grand Theft Auto VI, briefly visible behind a donked-out Vapid in Vice City's Stockyard neighborhood in the first trailer. A double checkered-flag emblem on its front fender hints it may belong to the Vapid Dominator lineup, and its quarter glass, windshield, wheels and fender shapes suggest it is based on the first-generation Ford Mustang.
Vehicle data via GTA Wiki (Fandom), CC BY-SA 3.0.