For stacking the square profile's rack (dark green on the pics) you will additionally need 20mm PE tube from your local hardware store. You can cut it to the length you consider sensible to have sufficient access to the compartment underneath.

I printed this with 0.8mm nozzle/0.5mm layer, it takes approx 170g of material. I set the Cura horizontal expansion coeffs all to 0 and this would lead to a very tight fit on my CR10Max, so you may have to make a test print first, or if not, try to tweak the fit with a hot air gun if too tight or with glue if too loose.

The red parts for the hex axles were printed on an Ender 3 with 0 expansion coeffs with 0.4mm nozzle/0.2mm layer. This part is amazingly stiff. 67g.

Creality

Ender 3

No

No

0.5