Note: I forgot to update but the thing need an hole/cable pass-through on the top of the tray or the top won't close.
Here's all the 3D printed part I used to do this mod.
There's are some part I used like the PCB for splitting the +5v USB power, but you can use whatever you need. (slide on top of the tray, and use “PCB Fix” to hold it)
The tray is design for the Pi ¾, but the other stuff like the DC/DC converter and the HDMI Splitter are specific, so you would have to use your own and remix the tray to your taste
Hinge should be printed 4 times and use a M2 screw to attached them to make two full hinges.