In order to transform a fixed stock AK into an Ak-100 style side folder, you must remove the original fixed stock trunnion and cut a slot at the front of the receiver and drill a hole at the front of the receiver for the locking latch. At the rear of the receiver, you must then make an angle cut of the receiver, followed by cutting a radiused section on the left side, looking from the rear of the gun forward, and drill a hole through the receiver on the right side. Then you rivet in the new AK-100 style trunnion, install the hardware and spring, pin in place, then put on the stock itself by tapping a pin through the trunnion and hinge of the stock. Finally, install the latch mechanism and spring. Done.