Yes, the drop base air cleaner drops the bottom of the air filter below the top of the FiTech, hence providing room for a taller air cleaner and/or making up for the 1 inch spacer under the FiTech. The main issue is that due to the shape of the FiTech, drop bases don't fit like they would a carberator or other throttle body, so you need to modify the drop base for clearance with the FiTech, or add a spacer between the top of the FiTech and the bottom of the drop base of the air cleaner.
Travis