The whole riser and a corner or the motherboard sled is removed with 4 screws. Plug the card in and one screw fastens it to this piece. Put in back into place and screw in. Its very secure.
As for hanging it and swinging it 90 degrees im not sure your aware just how heavy these things are. Once loaded with drives i struggle to lift mine. They weight a bloody lot. Your going to need a hell of a good hanging point and im not sure the case really has a good point to attach to unless your planning on welding stuff on. If you do come up with a solution i want pics. it should be interesting.
Oh an hi everyone im working with one of these myself at the moment for a site. Serious overkill for what i needed. But for the price
Im tempted to get a second just for home. Its currently balance on top of my desktop tower where i have been working on it. Work has been slow as parts trickle in from all over the world. Im in Australia and server class gear here is horribly expensive.
4 Nodes with 12x3.5" bays from pdneiman. At time of purchase i paid around a $1k plus $400 to ship it to Australia.
L5520's all around
Added Redundant Power Supply
LSI 9260 or 9261 per Node
96GB (12x8GB) RAM one Node
48GB (12x4GB) RAM another
24GB (12x2GB) the last two
With some cable management magic the 96GB node has 6x 73GB SaS 15k drives hooked up and the other 3 Nodes have 2 x 73GB or 147GB SaS 15k Drives.
One thing i have considered is can you stick a 6220 Node into one of these if you needed a bit more punch? Or something of the same form factor like a Supermicro 2+2
Edit: I have to give a huge thanks to you guys. I have gleaned a lot of info during the build process from this forum. I owe a lot of people a beer if your ever down under