First produced in 1964 ½, the initial design of the Mustang was largely unchanged until 1966. These ‘early’ 1st generations sparked the public’s fascination with the car – aided by a revolutionary ad campaign with product placement in movies and on television – and they remain best-selling options today. By 1967, the Mustang added weight and got a facelift, while power/performance continued to improve through the redesigned ’69-’71 models. Power output began to dip due to regulations in ’72-’73, and thusly sales suffered with these ‘fatter and lazier’ final years, although they’ve been revitalized in today’s market with the resto-mod movement. Performance submodels across the 1st generation include the Mach 1, Boss 302/409, and the introduction of the legendary Shelby variants.