Boil it, doesnt take long. If the meat is stuborn, dont fight it, boil it longer. Peroxide the small crap off. That tough stuff thats in the cracks like in the occipital condyles ect. If you are doing the bag method or the maceration method, it takes a long time. Add to that, its real nasty. I did one that way, never agian. Stinks, nasty, yuck, gross, puck, etc. Boiling is the way to go.