Grazing Muzzle + Mini = Disaster. HELP!?

That IS the best sort of muzzle. You can either attach the mouth-covering portion to his regular halter ( I reccomend leather, it will break away in an emergency) or put it on UNDER his halter (again, leather) so the clip strap on the muzzle and the throatlach are wrapped around each other. As always, check him a few times a day for injury or lack of water.