My understanding of the ART position is that it is technically a civil service job (GS pay scale), but you must be a military member in order to get the job (Reservist).
ART jobs are hard to come by in most units since they are handed out on a seniority and/or need basis. For example, if Major Tuffluck just lost his job at AA, has kids and a wife, he'll get the ART job before Lt Hardupfercash who is single and will just use the money for booze. That's NOT a rule, but it's just one example of how an ART job may be handed out IF they're available at all. I imagine they will be a little easier to come by in another year or two as the civilian job market continues to improve.
Lata!
Skyward80