I liked the idea of older Prusa x ends, that use two screws for each rod to fix it, but the implementation was rather weak. With iteration 2's solution (press fit, closed ends) it's a mess to disassemble the x axis, so I thought up a new robust version and since modifying one of the existing files would have taken even more time, I designed it from sratch and added even more upgrades like my clamped LM8UU holders!
Prusa's snap in LM8UU holders have one huge problem: motor- and idler-mount are supported via those holders, so the whole holder can twist unevenly and warp the bearings agains each other. This is avoided with my design.
The rods are fixed using one screw for each, tightening the built in clamps. Their screw heads are easily accessible from below and there are nut traps at the top. I made open end rod holes, to be able to push the rods all through. The system achieves a rock solid fit AND easy adjustability - what else you should need?
The leadscrew nut trap uses two bridges inside instead of a circular hole, so there's no "post-print-processing" (i.e. drilling) necessary in this point.
The design is entirely parametric, so you can even use professional leadscrews like trapezoidal ones with bigger nuts. I additionally attached STLs for use with metric trapezoidal leadscrews TR8x1.5 and nuts of 17mm wrench size (15mm height). For standard Prusa requirements use the "threaded rod" files.
There are thin support layers inside the M3 rod clamp holes that need to be drilled through after printing!
The STLs are generated for 0.25mm layer height - change the parameter in OpenSCAD for your needs.