I understand you, but the problem of "shaving off a bit of the frame" is that it may create other problems like more noise and/or less static pressure, neglecting their own existence by offering little improvements over Noctua existing fans.
But well, it's Noctua. It has to be perfect and they'll have a price that matches that attitude.
Please excuse my bad English.
Currently gaming on a PC with an i5-4670k@stock (for now), 16Gb RAM 1600 MHz and a GTX 1070
Steam / Live / NNID : jonxiquet Add me if you want, but I'm a single player gamer.