I just got my Mac Pro (bought off of e-bay). The original owner upgraded the RAM and Video Card. Anyway, When it arrived I heard the sound of a screw "floating" around inside the chassis. I opened it and tried to gently coax it out of its hiding place, but no luck. I fear it might be lodged under the motherboard, under the heat sink & fan assembly or underneath the area at the bottom where the RAM is. I am dying to turn this thing on, but I don't want to short something out because of the screw. Can anyone help me find the disassembly instructions or offer some advice. Thank You.