Carroll Shelby, after winning Le Mans in 1959, wanted to return to Europe to beat Enzo Ferrari at Le Mans with a car of his own design.
After sketching the proposed design on the floor of the Shelby America workshop, starting with the roadster chassis crashed at the 1963 Le Mans race, Brock removed the bodywork and placed a seat and steering wheel in alignment of where he felt that they should be.