Info:

Bought an used Toolless Mini Rack that came with only 4 of the guiding rails. Ended up needing 5, and designed this to properly mount the patch panel. 

The hooks on the 3d printed part are 1mm taller than the metal counterpart to prevent it from breaking under load.

The countersunk screw hole perfectly matches the screws from Ubiquiti's rack ears. I've included the fusion 360 file if you want to modify the design. Possible improvement would be adding a thumbscrew.

Printing:

Printed on PETG. I see no reason why PLA wouldn't work.

The supports on the bottom are optional. I glued them (easier to print) after printing was done, and they're there to prevent the rail from tilting.