With the OPF-G43x/48, RMRcc, we didn't merely raise the mounting surface to provide a platform for the RMRcc.  As RMRcc is longer than the G43X/48 MOS cut, the sight overhangs on the slide.  When installed, the bottom of RMRcc (with Trijicon provided sealing plate installed) is almost flush with the top of the slide so the sight is as low as possible.  We positioned the RMRcc towards the center of the plate as much as feasible, this is done to reduce the amount of unsupported overhang on the RMRcc's sealing plate in front.  RMRcc has a rubber gasket around its battery compartment to keep water and moisture at bay, which pushes the sealing plate downward.  This isn't an issue if the plate is of the same length as the RMRcc, but with an overhang, it creates a slight gap between the gasket and the sealing plate.  OPF-G43x/48, RMRcc's design eliminates the gap/opening between the sight and sealer plate, to the point of emulating a plate that's as long as the sight itself.  To wit, if the plate is as long as the RMRcc, it will make the installed height of RMRcc even taller, which is the very reason we chose to let the sight overhang.