Prusa XL nozzle brush scrubber with extra support against lateral force

This requires two additional pieces of hardware per nozzle:

• A 3030 M3 Spring Ball Nut 
• An M3x16 screw

To install:

• Insert the spring ball nut a bit to the left of the tool dock, with the hole towards the right.
• Insert the nozzle brush (facing left) and twist it 90 degrees.
• Align the brush (I highly recommend the positioner tool by @Surfalex2000), then align the spring ball nut below it.
• Use the M3x16 screw to secure the brush.

This version of the brush needs a slightly redesigned debris bucket to accommodate the left arm.

OpenSCAD file provided for further tweaks. To use it, copy the STLs from the original model and name them brush_orig.stl, brush_orig+1mm.stl, and brush_orig+2mm.stl

On my multi toolhead Prusa XL, I had the problem that the nozzle frequently made lateral moves across the brush for tool changes, and that these would twist the brush.

My remix solves this problem, at the expense of some additional hardware.