I used these motors on a project a few years ago. The way that I mounted them was there are 2 bolts that hold the motor together one when stock will stick out ~1.5" you can replace the 2nd one with a longer one so that you have 2 bolts to mount from. The thread is an M6 but I dont recall what the pitch is but I can look it up if needed. I also cut the profile of the face of the motor into the plate that it mounted to. Below is a link to some pictures showing what the profile was. I can send you the CAD model of the plate if you would like.
https://picasaweb.google.com/1147137...eat=directlink