This mounting system was designed for the Experience Lights Genius Pro 16, 8, and 4 port controller and receiver boards with LRS-350 power supplies and the MTM ACR4-18 Ammo Crate Utility Box which can be found on Amazon. The design consists of two board mounting plates that mount under the controller/receiver board, a power supply hat, and in cases where only one power supply is used, you can print the power supply plug that allows you to use the hat as intended. The larger mounting plate also has additional holes for mounting accessories including a set that fit the Falcon F8-Distro power distribution board. This design requires M4 heat set threaded inserts. 10 for the mounting plates if you use the power distribution board, 6 otherwise. You need 4 for each power supply plug if you end up using that as well.

This design was specifically created so no holes are needed through the box in colder climates where ventilation is not required. The power supply hat traps the entire board when the lid is closed. When closed, the board should have zero movement. 

I recommend PLA+ although PETG may be preferred for hot climates if used outside. As usual, dimensional accuracy is dependent upon the filament used and the printer calibration. Print test prints and adjust your scale to fit. 

The required heat set threaded inserts have a collar on the tip that should just fit in the holes. If the fit is loose, you should consider whether the print is accurate dimensionally and make appropriate adjustments.