WB, I've been wondering that too.. I have taken all the hooves of my last few deer, how you do it is boil some water and stick the foot in the hot water for maybe 10 minutes or so. then just pull the hoof off with a pare of pliers. but back to using them as overlays... theres really not much more then maybe 1/16" thick of actually keratin (finger nail) the hooves are mostly bone really.
-Fox