MMU3 Alternate cassette

I'm doing a partial, self-sourced “MMU2.5” upgrade and it looks like the commonly available “ultimaker” collet (6mm diameter) doesn't fit the collet holes on the MMU3 (5mm). In addition, it seems difficult to source the required 8.5mm x 2.9mm shaft. So I remixed the cassette with the following two changes:

• Use a 6mm M3 socket head screw instead of a shaft, and, 
• Use a 6mm collet (like https://www.amazon.com/dp/B0B2825TB4 ) Because the top and bottom of the cassette isn't quite the same (the screw is assymetric!) I've uploaded two models. Print both for each slot (5 of each). The same wheel is used.  

The screw just drops in place and is captured as if it were a shaft. Note that it is retained by a very thin wall (a single layer). There shouldn't be any axial load on the screw, so it worked fine for me, but some glue to hold the screw in place on the head side would probably be advisable.