 Shifting from Ford Falcon underpinnings to the Ford Pinto, the 1974 Mustang II shed nearly 14 inches of length and 13 inches of wheelbase from its 1973 counterpart.The smallest model of the Mustang ever, the 1974 Mustang II was 6 inches shorter than the 1964½ debut version.For 1977, Ford revised the placement of the Ford Thunderbird in its product lineup.