Once you have removed the two screws holding the lens assembly to the body of the camera, you can gently pull out the entire piece. Be sure to note how it looks after you pull it out because the metal piece has to go back on in a certain direction. There is one side that is mostly metal and the other side has little arms that hold the ends of both spools of film. The closed end is the side which joins up with the winding knob on the outside, while the open end is on the same side as the knob that is lifted up and allows for bulb or timed exposures. When you put it all back together after it has been cleaned, if you see through the lens opening without any obstructions, you have it correct. If part of the lens opening is covered over with the metal plate, you have the plate on upside down. The difference between the two is quite noticeable.