I print the cover from TPU 95A. Putting on the adapter is best when the cover is still warm, I put it on with the USB connector facing forward. It takes a bit of force.
I print the two-piece cap from PLA. The two parts need to be glued together.
shared project: https://www.pcbway.com/project/shareproject/Micro_Amiga_mouse_adaptor.html
The author marked this model as their own original creation.