Ive done a few Hog Skulls, I boil them in water mixed with Borax and Dawn Dish detergent. Dont be shy with the Borax and Dawn, Usually takes 3 to 4 boils changing the water, dish detergent and Borax. After you get them nice and clean be sure to pull the cutters and pull the meat out of inside the teeth, thats were your smell is comming from. When finished, I go to the hair salon and buy some peroxide and cover the skull with it and put it in the Sun for a few hours. Rinse and let dry for a day or two then clear coat it. Wont stink. looks awesome. These three I did a few weeks ago.