1966 Ford Mustang GT Fastback FacebookTweetPin 1966 Ford Mustang GT Fastback. In 1966 Mustang debuted with moderate trim changes including a new grille, side ornamentation, wheel covers and gas cap for this awesome muscle car. FacebookTweetPin Related 1967 Ford Mustang GT Fastback 5.0L 1971 Oldsmobile 442 1970 Plymouth Road Runner 1969 Chevy Camaro Z11 1967 Mustang Fastback 1967 Pontiac GTO Muscle Car