The support structure (underside that you are referring to) is most likely the same BUT it received EXTRA cutouts (during the stamping process) that removed material where the scoups mount that allowed the air to flow from the scoups to the ductwork. If you compare the underside of a flat hood to an original N96 hood, it's obvious, not so much with the ductwork installed. A sharp eye will spot a converted flat hood due to this. Some of the cutouts lay flat against the hood skin and personally I see no way of removing the material to duplicate the factory cutouts without removing the top skin first. Anyone done this successfully? I'd wager 99% of all who looked at it would not know the difference. Just my .02, jess.