Maybe the reason you can't get the trigger group out is because it is not supposed to come out. The trigger group is held to the butt stock by the long stock bolt, which is taken out by removing the buttplate and inserting a long screwdriver through the hole to unscrew the stock bolt.
The gun is normally disassembled by unscrewing the trigger guard screw at the left rear of the receiver and driving out the trigger guard pin, then pulling the receiver away from the trigger housing.
Warning. That gun is pretty complex and when screws are unscrewed and pins driven out, things tend to go wrong in a hurry with parts scurrying off for dark corners. I would tell you to leave well enough alone, but I have an idea you would ignore me.
Jim
