Every dual-purpose machine is custom-built just like a race car. Steel tube is measured, cut, and assembled on a chassis jig. Shock and engine mount positions are precisely calculated. It takes about a week to produce a chassis. Workers then pre-fit each component in the chassis to confirm that the particular set of components specified for each car is exactly positioned. From there, the long and complex process of installing and plumbing the engine, transmission, steering, and other components begins.