The home button would not always register a "click".
Fairly easy, I had taken apart iPhones before. The home button is one of the last things you can install. For a novice, it might be a little intimidating.
Take your time and organize the screws in a way you know where they go when you are putting it back together. Also be very carful, one of the cables on the digitizer likes to fold itself up and when you screw it back into the frame, the cable is stuck and you could tear it while trying to pull it.