Even for your nearly "rust free" area, the adjusters are known to "seize up"(won't back off easily) due to the constant heating and cooling of brake parts from driving. There are many different shaped brake adjuster tools for different vehicles, first time doing brakes can get quite annoying with getting the drums off. I have taken coat hanger wire and "shaped it" to fit thru the adjuster slot and push the pawl away from the "star wheel" adjuster to try and help things along(trial and error for shaping). Also in my "rust belt" area a big hammer comes in handy to break the rust "seal" of drum to hub and also jar off some of the rust ring that forms on the inside lip of the drum between the brake shoes and backing plate. Good Luck!