just go to the hardware store, and get some 1/4" hardware cloth (its like heavy guage screen) make a box and put deer head insinde. rodents can't get in, but all the bugs can. hand it in a tree and wait. nature will clean it for you. the more hide you can get off yourself, the quicker it will go.
my uncle places the heads in a five gallon bucket filled with saltwater and keeps it full. when the hide starts to decay, he lets the water evaporate, and as the water level goes down, the bugs pick it clean