Be sure to remove the gas tube, piston and spring, or you'll be banging the pin into it. Later, I just turned that pin around to plug the hole. Also, with the bipod, you only need to tap out the solid pin and the whole buckle flops open. Wish people would have told me these two key points before today. I read a bunch of forums and they were of little to no help. Also, if you plan on modifying an AK47 grip at the top to fit the Type 81, you'll need an M6x1 screw at 115mm long. You may need to open up the counter bore at the bottom of the grip, unless you get a Chinese screw.