Summary

I got this 220v remote switch for $20 on Amazon but it really doesn't lend itself to mounting in a way that supports wiring so I made this standard steel box cover-plate to mount it upon.
The recessed screw goes into the top of the box, The bottom hole holds both the bottom of the plate and the bottom of the remote switch box. The top-most hole holds the top of the remote switch box to the top of the plate. The 4 other holes are for the wires to reach out to the terminal screws.