Once a week, I use CCC to clone my three systems (OS drive only). I boot off an external drive that I previously partitioned with a 100G partition and 900G partition (or whatever the exact numbers are for a terabyte drive).
The 100G has Mountain Lion installed on it, bootable, only CCC and updates are on it. The rest of the drive is for combo updates and the image files CCC makes.
So, I shut down my Macbook, add the drive, hit and hold "option", and then select the USB ML install drive. I then open up CCC, select the Macbook's drive as the source, then for the destination, I select my previous image back up (for the first time, select new image).
This way, I have a weekly back up of my systems. Yes, I use TimeMachine too. I just like to have redundant back ups and bootable back ups. After I back all three up, I send it to Crashplan. Since it's sparse images, it only updates the changes, the first images took awhile.
So you can make a clone of your old drive, then when your new system is in, push the image onto your new system's drive. (I'd format it with Disk Utility first, your new system.)