It’s easily the best thing to come out of Dearborn since the 1932 V-8 Model B roadster. But for all Ford’s talk of Total Performance, it’s still clear that the Mustang has been designed and built to a price. The necessity of meeting cost goals meant that it had to share a maximum number of components with other models in the Ford line. Out of this situation sprang the advantage of an extremely wide availability of options for the Mustang, selected from the Falcon, Fairlane and Galaxie series. Briefly, it gives the customer a choice of four engines, three clutches, seven transmissions, two driveshafts, four brake systems, four wheel types and three wheel sizes, three suspension systems, and three steering systems. This seems slightly overwhelming until one remembers that only certain combinations are authorized, for either technical or commercial reasons. But it’s still very impressive and approaches the Tempest’s profusion of power team options. In two departments Ford even has the lead on Pontiac. Disc brakes are optional on the Mustang, and an independent rear end will be homologated and made available in small series for racing purposes.
The Mustang design was entrusted to Jack Prendergast as executive engineer under the direction of Hans Matthias, chief engineer of the Ford Division. The Mustang was built up on a basic platform steel frame with galvanized structural members and torque boxes. The frame was designed to carry all the mechanical elements on the under-side and all the body components on top. Structural rigidity was assured by a strong propeller shaft tunnel stretching from the toeboard to the rear axle kick-up, plus cross-ribs and reinforcements. The platform is so stiff that the chassis can be driven without a body. 
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