Yes, it was the belt dust that got me looking into the alignment, it was definitely the alternator that was out. But that alerted me to the 'recall' on the original alternator mount that can catastrophically fail so I figured the new alternator mount would straighten things out. That was good theory but the quality of the new mount was poor and I ended up doing a lot of customization to get the pulley in alignment, but even once I got that done I still couldn't get proper (or even close) tension. I'm concerned about wear in the adjusting arm bracket but I have a couple more tricks in mind if it gives me trouble.