RCX 1804 compatible arms for Hovership MHQ

These are arms I've made for the Hovership quadcopter, specifically designed to hold the RCX 1804 motors, or other motors that use M2 screws that are placed 6mm from the heart of the motor. The screws are sunken 2mm into the plate.
I didn't like the large mounting holes that the original arms have. Off course it's nice for making it suitable for more motors, but the small screws don't have much to hold on to. I've added a grove along the middle of the arm, branching out to the side, for guidi