I'm sure the idea of cutting anything becomes a "hack job" by some definition. Interstingly, if it's done right, the input trimming means absolutely nothing to the trans, or any use after, because of the parts available now. Mainly the hub/pilot bearing. It's less intrusive, les damaging, and less permanent than cutting two large holes in structural steel and screwing a cover plate over it. My point is, they are both modifying existing parts to make them work. Neither are "top notch" engineering, but bastardization of existing technologies to improve the performance of the vehicle. Top notch engineering would be everything fitting without any modifications.