If you want to cut molding lines, in the butt-stock or above the ramrod channel, for example, one of the easiest ways is to use a triangular file or the edge of a half-round file. Draw a line where you you want it, then slowly work the file along it.; the length of the file helps keep the line straight and the depth increases fairly slowly at first, so there is plenty of time for correction. Many (most?) originals have file cuts in the butt-plate, so I assume they were doing something similar. I'm sure someone will correct me, as I'm just a beginner myself, if this technique is out of bounds. You can do the same thing on the cheek-piece, although a handsaw also works there with some care.