Fusion drive upgrade: how to get my installation back afterwards? I'm planning an upgrade of my iMac 27". An SSD will be added and combined with the existing HDD into a Fusion Drive. I have just reinstalled everything recently and like to keep this installation. 
My plan is to clone the HDD to an external drive using SuperDuper or something along these lines, the install and create the Fusion Drive and afterwards clone back onto the Fusion Drive.

Will this work? Or will cloning back "destroy" the Fusion Drive setup?
Personally I did the same thing. No, Cloning and restoring the clone to the fusion drive will not "Destroy" the fusion drive.