All the tools that came with the Mini Kit fit inside this box, including the tongs (when closed) and also a printed scraper! (https://www.prusaprinters.org/prints/58211-print-bed-scraper-no-supports)

The print bed can still move freely and has enough clearance. The box hovers approx 3mm above the ground. You need to move it into the space from below and then hang it into the aluminium extrusion.

Inspiration:

Used this box as a first draft for the size and the details (chamfers and radii): https://www.prusaprinters.org/prints/41071-storage-boxes-for-the-prusa-mini

Used the mounting geometry of this side mounted spool holder as a template but improved the fit and printability: https://www.prusaprinters.org/prints/49367-prusa-mini-side-spool-holder

I printed it with supports under the mountings but I think that wasn't really necessary.