I thought the same thing, but the mounting system for the PSU (at least on the PC60) is a bracket screws in just to the back of the PSU and the bracket in turn screws into the back of the case. The bracket does not cover the entire unit, only the back. All I had to do to get my Enermax in was take off the bottom fan grill so it could slide through the case opening and then screw the grill back on once the thing was inside, which was a little bit of a pain, but well worth it😀