Yes, the case is just a pressure fit, and you can open it by carefully working the screwdriver around the inner seam. You will hear a couple of snaps, which are the fittings separating. Just don't work it too quickly, or you may break them. There are plastic tools that are also made to do this kind of thing, but if you are careful, a broad, flat head screw driver works fine.
The reversing mechanism is easy to spot and reset, and then oil. Good luck if you have the same problem.
barryo
August 2009