You are very welcome! It's good you stopped to remove the butt plate, I don't want you to damage the screws. With "original disc" I meant the original disc of the rifle, not the added disc with the "MP" marking. The area between these two discs is important, I have marked the area in the photo, there should be the branch of service (H, M or L) marking. Maybe it's still slightly visible when you take a good photo.
Stock Kopie.jpg