The worst stripped screw in the iPhone4

So, I already had repaired my home button a couple of months ago, and I now wanted to replace the display since it's got a couple of cracks, but the screw holding the logic board (the one you're supposed to remove in step 16) is stripped, and because of its placement it's just a nightmare to try and unscrew it: nail clippers are pretty much useless because of the really limited space around the screw, and I just bought a set of micro-screw extractors but the smallest one is still too big for the screw. I was wondering if anyone had bumped into the same problem?

Thanks,

I.