Hey, for the last few years i have had nothing but trouble degreasing my skulls. I simmer at very low temps (below 200 degrees) and use soap when i simmer. After i have tried dawn in water for months with no success, I then tried dawn in water at temps as high as 160 for weeks with no success at all. Some of these whitetail skulls are almost completely covered in grease others just have some spots on the forehead, but no matter what i do the grease doesn't go away or even get better. I've also tried borax, acetone, and many other methods. What should i do?