Semi-feral cat notoedric mange?

[rock_doc]

We live in the country and look after a semi-feral cat that we have befriended and somewhat tamed over a period of about a year (enters house, sits on lap, appreciates petting) though it mostly lives outside (not litter trained).  The cat has hair loss and blisters that began on the ears and have spread in front of the ears and appear to be spreading elsewhere on the face.  We don't think we could get the cat (Little Henry) into the vet (not that tame) but it really seems like something needs to be done to treat this.  

[Aleda M Cheng, D.V.M., C.V.A]

It does sound like mange of some kind, whether Notodectes/scabies, demodex, or other mites.

You might be able to treat his ectoparasites using Revolution topical (from Pfizer).  This product is placed between the shoulder blades on the skin, but instead of applying once per month, you would apply once every two weeks for 6 weeks.

If Revolution is not effective, you may have to bring Little Henry to a vet for a skin scraping and appropriate treatments, such as Ivermectin, lime sulfur dips, etc.

[rock_doc]

I didn't manage to finish with a question.  My question is, how would you approach this problem?