I had a problem on the screws with the springs still spinning. While not having this problem the first time to dismantle the board was because I did not tighten the screws on the plate (bolts real logic board, not the one you used to hold the heatsink to the motherboard) before reassemble. If you encounter the same problem, not necessarily stripped screws, but the real piece connected to the motherboard is loose and just keeps turning. To get the pressure I used tweezers and stopped while turning until they got out and took me a while. Moral of the story: tighten the parts are actually connected to the plate before reassembly. Sorry, I do not know how else to describe the types of screws used, but studies joins the board and that's what broke loose.
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