Ok here is how I did a couple of deer mounts this past fall. To start with remove the skin and excess tissue.Then get some Arm & Hammer Super Washing Soda at your local supermarket it's used for washing clothes. Add a cup of this and some Dawn dish soap to your water. Don't boil the skull just simmer it. I cooked the deer skulls 2 1/2- 3 hrs. A coyote being smaller may not take as long. This method worked great on my deer heads, the teeth barely even got loose. The real time saver is using a pressure washer or car wash to remove the cooked tissue from the bone. You have to be careful around the sinus cavities or you can damage the thin bones with the high pressure. Then get some Jolen Creme Bleach in the cosmetics department. It's a peroxide base bleach used to bleach facial hair, you might try to add a some water to thin it a little to help spread it, leave it on overnight. Regular peroxide thats used for cleaning cuts and scrapes is weaker than the stuff used for bleaching hair. All these products can be found at most Wal-Mart or super markets. It worked great for me, hope this helps.