Get a straight edge and run it from the balancer to the PS, I found the difference to be about 5mm, we drilled out the bracket so the whole PS assembly could move forward 5mm, the job took a couple of hours to do but now the 2 pulleys align perfectly.
And it was only the PS that was causing issues, the AC and ALT are fine.
Give ROSS a call and see what they say, its a common problem, albeit a easy fix if you modify the bracket.