Here's Apple's admission of the NVIDIA 8600M GT graphics processor issue, and promise to repair free of charge if failed within 3 years of purchase, even if out of warranty: http://support.apple.com/kb/TS2377
these connectors can be very loose and break from the logic board. I have left this one connected until after the next step, at which point I can pull it out more carefully and easily.
-Dan "The Berkeley Mac Guy"
If you pull it off, find a place that does micro-soldering. What a pain!
Check your local Chinatown, you might find someone who worked in an electronics factory, like I did. Or scrap the thing and check on craigslist.org for a replacement.
when going backwards, be sure to check the previous step before performing this one, to line up the black plastic bits to their places - just inside of the metal screws. if you attach the display without lining them up, you will have to remove it again to re-align them.