signs of a bad steering box or ps pump?

You have a seperate belt for the power steering pump. By removing it the steering will become much harder (two hands), but you will take the pump out of the equation. If the noise goes away, it's the pump. By the way, when you "turn the wheel all the way" you aren't holding it against the stops are you? That pump will complain (make noise) if you do that. Try backing off an inch.