I was delighted by Chri's endstop holder - elegant looking and a real improvement over the standard. It fits in tighter spots and should hold adjustment better. I needed an SAE version though, so I threw together an OpenSCAD version.

The included STL is for #6 SAE screws and nuts (5/16" wrench size). The SCAD is there if you want to fiddle.

I removed most of the 4th wall on the switch from Chri's design since it does nothing - the bigger gap also makes it easier to get the switch out if you need to do so.