Hi, I have a 27'' IMac Mid 2011 It currently has the standard HDD in it & I'm going to install a new SSD. I would going to keep both drives in the computer as I would like to use the HDD for storing music, pictures etc. But on the SSD I would like to have the OS on it. How do I go about transferring the OS x from the old HDD to the new SSD? Really would appreciate any advice! Thanks. Sam.