1U Mount, sized for #10-32 Bolts and Nuts for the front and #6 at the wall (because that was the prevalent size for 50lb wall anchors at a convenient hardware store).

Uses pocketed nuts, so no worries about stripping out the plastic.

Bracket top is open so you can remove the cables with the panel for service. You can flip the panel over for punching down right on the wall. (Probably not a good idea unless they're really well anchored, I chickened out on doing it with 50lb drywall anchors and used a ladder step instead.)

I included the 10" panel templates I used for installing my anchors as DXF (I laser cut it out of chipboard) and as a 1:1 PDF drawing. I also included an untested 19" set, and you'll need a big printer for the PDF of that one.