This write up is spot on but there are some small variations with a 2012. Nothing that will affect how you do this however. I read through this DIY guide a few times to understand what I was getting into. Luckily for me I have the great fortune to live in the same city as Wheee! who offered to help me with this.
We did 20mm rear and 15mm front in his garage last night on my roadster. By we I mean he did it and I assisted breathing a huge sigh of relief I could watch how its done properly. Could I do it now myself? Yes. But it was nice to watch someone with the know-how to go through it.
A little over 2 hours to do the whole thing and the car looks great. Pics to follow in an album.
Thanks Wheee!