Adaptors for 608 bearing wheels ( Guinea Pig Wheelchair)

There is this wheelchair for guinea pigs published on thingiverse. I've made a type of adaptor that uses 608 bearings, but the original wheelchair cart must be printed at 150 % size for this to work. The guinea pig we made this for, would fit better in this size cart.

You will need:

This thing https://www.thingiverse.com/thing:3462835 printed at 150% size.

M3 hex nut - m3 x 20mm screw and washer

608 bearings

The adaptor STL components printed in PLA + or PETG.

The other cylindrical bit must be printed using a .25 mm nozzle and 98A flexible filament if possible. Any filament would do as long as you can print it well.

The wheel printed in TPU 98A and an infill of 40%.