Just days before Apple presented the Fusion Drive macs I got a brand new SSD and a hardwrk adapter kit so I was *really* interested if I can use the Fusion Drive technology in an older mac.
Turned out: Yes. So I installed a fresh 10.8.2 on an SD-card and did the magic diskutil commands in the terminal to fuse the 240GB SSD and the 500GB HD.
It is basically two steps in the Terminal:
1. Build a logical volume group from the two drives:
diskutil coreStorage create <lvgName> <disk0> <disk1>
2. create a volume on the LVG (the 111…555 must be the UID of your logical volume group):
diskutil coreStorage createVolume 11111111-2222-3333-4444-555555555555 jhfs+ <lvName>
Now mine looks like this:
Note: You can’t open a terminal from a rescue partition so you need a fully installed 10.8.2 on an unaffected drive.
I installed OS X on that, restored the backup from my trusty FreeBSD server with ZFS and netatalk and now everything is up and running (fast).