On the belt tracking issue, I put a new timing belt on today and it tracks perfectly down the middle of the pulleys. The old belt must've been unevenly worn (I tried loosening the tensioner with the old belt, but it didn't fix the problem).
I also had a hard time getting the old tensioner off. Luckily I had a couple spare nuts of the right size to fit the tensioner stud, so I was able to double-nut the stud out. However, the original tensioner occupied a lot of space on the stud. In order to get two nuts on there sufficiently, I had to grind them both down a bit so they were slimmer. It was a bit of a pain for something that should be so simple. Then, when I went to put the new tensioner on, since it takes up less length on the stud, the shoulder on the stud stuck out and made it impossible to tighten down on the tensioner. I had to put some washers in there as spacers in order to get the tensioner firmly tightened. It all worked out in the end... but it was a pain.