You can convert a flat hood to the N96 hood (I've done it before), but you need to know exactly where to cut the openings. When I did it, I made some paper templates using a damaged N96 hood as my guide. The scoops are not the difficult part - what's more challenging is cutting the underhood braces in the correct locations for the airbox. Some of the areas you need to cut are right up against the hood skin, so cut too deep and you have a hole in the hood.
In short, it can be done but you need to know exactly where to cut.