For those of you who do not have a Factory Shop manual.... it goes into great detail and has several special tools for doing flush, etc...
Larry and I will never change our minds about doing this according to the book.....the inside of an AC system is a severe work area.... and anything not supposed to be there can really mess up stuff.. and require expensive parts and labor....
I do understand micro climates.. it is amazing how a few miles can make major differences......