Welcome to the reason you should always buy a kit. Do yourself a favor and track down a set if JIS (japanese industreal standard) phillips screw drivers, they won't make a mess of the phillips screws in the Japanese kits. Keep track of what goes where and make good use of http://www.raptortechnique.com

While you have it apart spin all the bearings with a pencil and any that feel notchy or gritty replace.