I needed a way to mount a Raspberry Pi camera and I had several parts from the Modular Mounting System (https://www.thingiverse.com/thing:2194278) All I needed was a way to interface with the 3030 extrusion of the Prusa MK3, so I cut the mount off. I used 3M VHB tape to connect the two. 

I printed this in Inland Red PET_G, settings really don't matter. 

Here is my OnShape model.