uh, its pretty easy. once you get the gearbox seperated from the trigger and everything (assuming you've gotten this far...), you pretty much just take out the screws. But before that, theres a little catch inside that you can reach with an small screwdriver that you have to release in order to relieve the spring. Inside one of the many slits (this one should be on the right side i believe, if the gearbox is pointing left), you should be able to see it.
But don't do this until some more people respond, this isn't my thing that much. i just know this from watching my friend do it to my Mp5 over and over. I probably wouldn't touch it unless you FOR SURE know what your doing, cause you could end up with parts scattered around that you dont know where they belong to.
