On my first cp, i used l-brackets like above (I think tey were actually cisco rack mount brackets) that I kept fastened to the CP, and unscrewed from the inside of the cabinet when I would need to work on it
On my current incarnation, I have 2 latches(one on each end of the CP) that are similar to what you would find on a toolbox for example. These are screwed into the cabinet, and the metal "loops" that they hook into are attached to the bottom of the CP. I just have to flip the 2 latches and the CP is ready to be removed or flipped up to work on.
I'll probably either add an identical set of latches to the under side for stability- although with just 2 it's rock-solid- or find a set of latches that are wider and stay more secure.
I still need to work out some issues, as the new CP cuts into the bottom area of my bezel, so I need to shorten that. Also I need to find something to cover the front of the CP, some sort of box, or maybe a hinged piece of plexi to wrap around and cover any stray wires
I'll post pics tonight of my previous and current setup to try and make it clearer