Hello, I have a 2012 15-inch MacBook Pro that i'm upgrading. I'm replacing the ram and upgrading the 5400rpm hdd with a SSD. What I plan to do is put in the SSD in a caddy, and put it in place of the current dvdrom. I plan on having both the old HDD and the new SSD. Can I put the SSD in the secondary hdd position(where the dvdrom was) and clone the first hdd, than format the old HDD. Can I run OSX off the SSD in that second slot. Or will I then have to swap the SSD to the first position and than move the old HDD into the caddy? I'm hoping to only open up the macbook once if possible. I also dont have one of those cables that i can connect the sdd via usb and dont plan on buying it for a one off upgrade.