When you say:
Remove the following ten screws:
Two 8 mm 5-point Pentalobe screws
Eight 2.5 mm 5-point Pentalobe screws
Do the 8mm & 2.5mm dimensions refer to the LENGTH of those screws, or the size of the pentalobe? That is, are there other sizes of pentalobe drivers like there are for hex, phillips and torx? When only one dimension is provided, it is usually the socket/driver size, not the screw length, maybe since the length cannot be seen when the screw is installed.
Can I suggest that you clarify your instructions so folks are confident they are only in need of _one_ pentalobe driver?
Nerdily yours,
Larry (whose iPhone 4S can now get through a day without 6 recharges thanks to ifixit.com ;-)