Yep boiled the heads, first skin everything that you can off of the head and then boil it until all of the crap starts to fall off, I usually let it boil for a while the try to pull some of it of and then return it to the boiling water, then I spray it out and off with a hose or even better a pressure washer to get the remaining head matter off the skull, just be careful when using a pressure washer, but it works great. Next we use a powder from a taxidermist magazine called magnesium carbonate and make a pste with that and high % peroxide, i cant remember the % but you can not buy it at normal stors, i think its 20 something %, after you make the paste slap it on the skull, cover everywhere that you want white and let it dry for a day or two until it will flake off, and thats all, its a pretty simple process.