This is a model to hold the MMU2S flat. At this angle it is easier to see into the inside of the MMU2S. The MMU2S is also pushed back 1 inch for clearance of the PTFE tubes if the printer is printing at its max height.

I printed the part out of PETG with 3 perimeters and 20% infill.

Edit: With the flat frame holder the PTFE tube could be bent into weird angles when printing at the max height. I added a new version with a 25 degree angle to keep the easy viewing angle into the MMU2S, but to try and resolve the bend issue. If you would like a different angle please let me know and I can make the file.