So here is the latest design, very small if any changes.
Haven't had a chance to test rivets/flange nuts.
Again, 3mm acrylic and dome nuts at the bottom, grub screws in between and flange nut/rivet at the top, These are just my recommendations, since the design is available to all, you can do whatever you want

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I have added a compatibility table to the OP, if you have any requests or can help in anyway it would be great.
Any suggested design changes? Can someone please check the dimensions.
If someone knows how to operate a 3D CAD system, can you please layer these as 3mm sheets and post a screenshot, or PM me on how to do this. Thanks!