BTU mod XL "Thumb Trackball" Ploopy mouse

I found ball-transfer-units (BTUs) provide a smoother mousing experience. Inspired by bomtarnes. Details about the BTUs I used for this model:

• R053010810 Bosch Rexroth Ball Transfer Unit
• US Store: https://store.livhaven.com/r053010810-bosch-rexroth-ball-transfer-unit
• I have attached a screenshot of the data sheet for posterity

As for the “XL”: The tail end of this model is 170% the length of the original model. In total, it adds about 4cm of extra space for your palm to rest. It's not pretty, but it feels way better for my hand.

The parts are NOT backwards compatible because the BTUs extend down into the base.

Additional info after a few weeks of use:

• This mod feels great, but is significantly louder than the stock bearings. Beware if you want to use this mouse in a shared space as it may be disruptive.
• In search for something quieter, I experimented with some nylon BTUs. Specifically, “MNB001 NL-8H 8MM Nylon”. Regrettably, these nylon BTUs were a bust - they were both loud and felt worse than the stock bearings.

To quote, bomtarnes, “Note that the ploopy files are originally licensed under CERN-OHL-S which prusaprinters does not support; I have chosen what  I believe to be an appropriate license.” I have included a STEP file.