Apparently not too uncommon, my home button was failing. Very annoying.
Disassembly was a breeze! Putting it back together is like when you get a big package full of stuff and you need to return it. You can't get it to fit right, but it has to be perfect. It took almost 3 hours to complete. No room for error, it is tight in there.
The screws are so tiny! I'm 40 and have been building computers since before I could drive, and this was a challenge for me. While I feel a great deal of satisfaction for getting this done, it was not fun. Only do this for yourself or a loved one! I would assist a friend, but only with advice.
I now feel more comfortable with the inside of the device, so I'm no longer going to worry about getting a scratch here or there since I know I can repair it myself with the right parts.
Flathead 3/32" or 2.5 mm Screwdriver
SIM Card Eject Tool
iPhone 4/4S Liberation Kit