I take as much as I can cut off. I do not scrape it. Do not forget to poke, drill or cut a hole in the lower back of the skull, unless you can go in the spinal cord opening, to take out the brains. I use a piece of wire and bend the end in a U shape and det as much brains out as you can. After simmering for a while I work on the brain cavity again. Be sure and pour the water through a screen if you loose some teeth, they can be glued back in later.