Pulled the whole rear subframe out and dismantled everything. Welded the toe links and finally installed the Energy Suspension bushings I've had for over two years. The bearings on one of the axles were going bad so I replaced those as well. Had to cut the toe adjuster bolts to get the trailing arms out. Other than the bearings, I found nothing obviously wrong. The bushings seemed fine.
When I reassembled everything, I set the toe for max toe out like it was when I tore it apart. After reinstalling the subframe and taking a short drive, I checked the toe. It was 5/16 toed out. So I went from 1/2" of toe in to 5/16" of toe out. Something was clearly out of whack. What exactly it was is a mystery to me.
I'm surprised how much of a difference the new bushings made. All the odd clunks and noises from the rearend are gone. The ride is noticeably improved as well. It's like driving a new car!