Did you use a belly board? Hold the board about waist high and let it drop straight down on the nose a couple of times on a hard surface. Either hook the nose on something or have someone hold it while you try to remove the board. I've done that when hides stick to boards, even with a belly board. For those times I let them dry to long fur in, I have used damp newspaper wrapped around to loosen them up so I could turn them, not sure it works fur out.