OK - Here’s what I think would make a potentially good solution. A remix of a couple of different set-ups on Thingiverse. My Fusion360 skills are meager, so chances are I’m not yet up to this challenge so I’ll share it here if anyone wants to take it on. It would take a lot less time to remix parts then to start from scratch.
I’m partial to the dust shoe on the Suck-It system. So, here’s a Thingiverse link that has the same shoe and connection system, but it’s designed for a Shapeoko.
Now, of course the pieces that attach to the part shown above that is blue with the magents - it won’t easily work for a MPCNC - it requires aluminum channel attached to the gantry. However, the distance between the ends of the blue pieces are very, very close to the distance between the two lower smooth rod clamps from this design:
I like the idea of the smooth rods over the plastic pieces in a channel as on the Suck-it, as the plastic sometimes wants to bind a little on one side or the other as you are adusting the shoe horizontally.
Someone would just have to create an adaptor that attached to the shoe, that would let hook to the smooth rods attached to the gantry. You’d then have a shoe that is not supported by the router/tool holder/vertically moving parts, is stationary vertically - allowing the cutting head to go up and down with no force being put on it by the brushes, is adustable to the height of your materialand which has magnetically attached shoe for easy changing of bits.
Am I missing anything here?