May I ask why you are so certain he doesn't have pox? I know you have it down there; I helped someone this winter with some poxy Boston park squirrels (not the Common). I have never seen big lumps and bumps with mange - this looks like he has pox which compromised his immune system and allowed the mange to get it's teeth into him. If he was one of "mine" I would be treating him for both. Acyclovir works with pox. If you are interested in trying, let me know.