I haven't used Blue Job, so I can't comment much on it. I have repeatedly seen the words "elbow grease" associated with it though. I stumbled over this product at NAPA:
I kid you not, this wipes the blue off of my pipes with about as much effort as wiping up water with a paper towell. I think the can cost 5 or 10 bucks. It is a big chunk of wadding saturated with some kind of polish. Just tear a piece off and wipe it on. Then, wipe it off with a soft rag. It does not prevent re-bluing, however. Tuning my carb did that. Blue Job might help with that issue? Anyway, I would heartilly recommend trying Nevr-Dull. It makes this chore a snap.
Good Luck,
Jason