I wanted to install an SSD harddrive in the mac mini to speed things up a bit.
I followed the iFixit hard drive replacement guide för mac mini's late 2012 and it worked out perfectly.
The only thing that was a bit tricky was the metal encasing with the wifi-antenna attached to it. I could not manage to get it to fit right back the supposed way. It was simple a couple of mm to big. Using the two screws on the sides and working with them slowly and simultaneously I could eventuella pry it down in the right spot.