Sidewinder X2/Genius Pro - stock spool upgrade

Hello all,
my next small project --- a SWX2 stock spool upgrade.

Reason for this project was - I have some spools that are far wider than the normal stock spool holder allows. Thus I needed to replace the stock rollers with longer ones.
This was v1.
Yesterday I saw a video, where the new Genius Pro/SWX2 solution has been presented :
https://www.youtube.com/watch?v=hxdyY4i-vtc
and I thought.... ball bearings like introduced in the video would additionally reduce the fraction and smoothness - especially when using bigger, heavier (>1kg) spools.

That is why I have created new rolls --- over 11 cm wide, which accept the 605 type ball bearings.

Requirements to mount (BOM):
--2 x of the here included rolls
--4 x M5x10-15 screws
--4 x 605ZZ (or equivalent size) ball bearings. I have "noname" ABEC3 which I found on Amazon. These don't need to be the highest quality but need to be "good enough" with less friction.
--4 x M5 nuts (optional loctite or anti loose nuts)

Remove the stock screws and rolls, add one ball bearing from the inside per each of the 4 mount points, tighten with M5 screw and nut. Check that the ball bearing can rotate freely. If not -- add an apropriate washer on required side of the ball bearing to allow it to rotate freely.
Once all the bearings are installed -- put the rolls between both sides of the spool holder walls and "squeeze" both side in, so the ball bearings are inside of the rolls. Tighten the screw on one of the spool holders to the frame after it is adjusted.

If you require a different width you can easily adjust the Z-length only in the slicer. There should be enough "wiggle room" for the screw and nut inside of the roller even if you want a little bit shorter version.

This exact version of the new spool rollers has also been successfully tested with my "Bigtreetech Smart Filament Sensor" mount posted here :
https://www.thingiverse.com/thing:5190559

P.S. Depending on how good your printer is calibrated -- if the ball bearings are not going inside of the rolls you can increase the X and Y size in the slicer by 2-3%. For a perfectly calibrated printer it shouldn't be necessary and with a little bit of extra pressure these should slide in.