I think you misunderstood my problem. The surface of the CG that mates with the surface of the case, and the surface of the case, were not even close to matching. Large gaps were present where portions of the CG were not contacting the case when the CG was installed. The only way to fix this is either file the CG or the case or get a CG that fits better. My point was you need to be very selective and efficient with your filing so that you don't end up with the CG being too close to the case.