Looks great. I'm not so fortunate to be able to run disks larger than 2TB due to the age of my LSI HBA. I can't moan too much though, as it was free. In a lot of respects, mine could really do with an overhaul similar to this as it's 2009 hardware. (phenom II x4 with 4GB DDR3) The icydock backplanes are great.
I nearly ran into this problem on mine as my SAS expander card uses a 4x slot and my board only has 2x x16 slots and x1. Both the gpu and raid HBA used the x16 slots leaving none for the expander. Thankfully, the expander I chose doesn't need to be run from a pcie slot and can be powered directly with a molex.
It's tough working with Enterprise hardware and real servers then going home and using consumer grade parts. I don't quite have the same budget at home as I do at work

Thankfully you lucked out being able to power it from a molex.