13:1 gears in APS box

Has anyone been able to fit 13:1 gears in an aps box. My gears don’t fit in the guide i was wondering what is the easiest way to shave it down .5mm pictures for details


I’m sure there is a way and a Dremel and sanding disc springs to mind but…

Buy new gears? It seems a waste but I view it as a better outcome that cutting into your new box