Abstract: A method is provided for machining the stainless steel automotive exhaust components that allows such components to be machined in high volumes and at a reasonable cost. An exemplary embodiment of the method includes the steps of: (a) supporting the manifold on a work structure; (b) clamping the manifold to the work structure; and (c) machining the supported and clamped manifold; (d) where the clamping step includes the step of clamping each of the plurality of inlet coupling flanges of the manifold separately; and (e) the machining step includes the step of machining the interface surfaces of the inlet coupling flanges. In a more detailed embodiment, the supporting and clamping steps orient the planes of the interface surfaces of the inlet coupling flanges of the manifold perpendicular to a spindle access of the milling machine.