Can you switch the top case and keyboard to a different language? I really regret not getting a CTO 2012 macbook pro before they went to the retina only. I was wanting a different keyboard on a MacBook Pro that has an nvidia 650 GPU and a 1680x1050 monitor.

Once when I took my computer in to an Apple store the genius bar guy offered to switch my keyboard to a US keyboard; so, that would imply that it is possible. So, does anybody know definitively if I can just get a MacBook Pro with a US keyboard and then just find the appropriate top case and keyboard with the language I want and then switch them out or should I just keep hoping one shows up refurbished?
I have done it on a PPC 17" MBP equivalent and also on 2011 15" MBP. It needs plenty of time and care. Say 24 hours for first time. Look on iFixiT for "how to s" and read them through carefully two or three times. My original reason to do so was to change keyboard from Spanish to GB English.