Summary this is just a slight mod to my original upper Z mounts. the 1st ones I did the outer face hangs off the edge of the frame 2020 extrusion on top. Annoyed me so I moved the mounting screw in and jogged the face a tad so it stays inside the frame structure. As before I have mounts for the nuts os no wrench is needed in a tight spot to tighten the rod caps (do not over tighten as that will bend the motor mount down and throw the whole printer out of square) extra screw mount in the back if desired (though not really needed) return down the back to keep the mount square to the frame easier. For the offset style Prusa i3 clones.. not for "inline" where the rod is in plane with the screw.