I had to rework the model to meet my needs.
I did this model back in 2020, during lockdown, so I couldn't go out to get the threaded rods. Therefore, I removed the holes and increased the notch on each frame so that they fit better in each other, like Lego.
Also, my switch does not support PoE so I had to rely on the normal USB power of each PI board, that's why I had to make a cut on the back of the frame so a USB C 90 angle adaptor would fit.
Overall, this model is excellent.