I needed to use sheet metal screws to mount my U7 Pro XG on my patio. I made a mount that allows the use of whatever screws you need (the larger counter-sunk holes). You can then attach the stock metal bracket to the printed mount using M3X8 screws. M3x10 might work too. Use the A/D wall mounting holes on the metal bracket that is included with the AP.

Happy Printing.