If you are talking about the rear duct/cover that wraps around the air box and doubles as part of the air filter retainer, there really isn't much advantage to do it. You can actually completely remove the cover and replace it with a bracket that holds the top of the air filter in against the air box. You can make the bracket or purchase one from Sean Morley (I think). If you are going to go that far, you might as well remove the internal air restrictor if you haven't yet.