This past weekend I swapped out the DVD drive for an extra 2.5" drive slot in a late 2011 17" Macbook Pro. It was slightly nerve-racking because the pictures on the ifixit instructions were not the same as the inside of my MBP (I think they were the 2010 model) but after some careful observation and playing around there, I was able to remove the dvd drive, swap in my secondary drive in the 2.5" adapter tray, and get all the screws in with everything held securely in place. The only thing is that there was this small metal pronged piece that popped out of the laptop and I don't remember where it went. Things like screws I was paying very careful attention to because I was anticipating having to put them back but this thing just popped out and I have no idea where it went. Everything is very secure without it and really, it doesn't seem like this piece is strong enough to secure anything anyway. So I closed up the machine and started up. Everything works fine. Having finished, and thinking back about how well designed the interior of the machine was compared to other computers I've worked on, and remembering articles that claimed that Steve Jobs obsessed over even the inside of the computers, I started to get nervous that this piece was somehow important. Maybe it grounds something to something else to prevent the electronics from shorting? Can anyone please help me put this piece back in? And what does it do?