Production of the GT began in 2004 at the Wixom plant in Michigan, where the supercar would also receive its supercharged, 5.4-liter V-8 mated to a six-speed manual transmission. The development process included input from Carroll Shelby, the same man who helped develop the GT40 race car back in the 1960s. Ford built 4,038 GTs through 2006, with only about 300 sold outside the United States. The production also included a Heritage Edition series, of which only 343 were built. These special-edition supercars came with standard equipment, but the GTs regular paint and stripes were replaced by a Gulf livery similar to the 1969 Ford GT40 that triumphed at Le Mans.