I have a G-Tech RAID (2 4TB disks). I want to break this from the current RAID strip into 2 independant disks, and enable FileVault2 on those. I've done this in the past with a different G-Tech RAID... but I can't for the life of me figure out how to do this using El Capitans new Disk Utility. It seems, well, horrible. What to do?