Removing the x-axis end pieces on the Prusa MK3(S) is difficult as they are a very tight fit.
This tool allows them to be removed safely and easily.
x3. M6 nuts (10 mm spanner)
x2. M8 washer (outer diameter 15.9mm / thickness 1.4mm)
M6 threaded rod - length 36cm
I used M8 washers as opposed to M6 as they spread the load into the PETG parts slightly better. You could use a dab of glue to hold them in place, but this is not necessary.
Screenshot shows the dimensions of the printed part, the countersunk hole is of depth 1.5mm
The parts were printed in PETG, using 5 perimeters and 40% grid infill.
When assembling, be sure to orientate the nut on the end as shown in the picture so that it slots into the slot on the right hand side of the x-end-idler plastic part. To remove the x-end-motor / x-end-idler from the rods, simply align the tool as shown and gently turn the nut nearest the x-end-motor to ease the parts from the rods.
The author hasn't provided the model origin yet.