People -
Recognize: belts are easier to replace than these bushings.
Either go whole hog and re-enginerd it,
or perhaps do as I do: install the belts just tight enough not to slip, verify with tension in under 100 miles of run-in. Next, don't touch it.
Then when they chirp or squeal, adjust them one last time, and add them to your next oil change driven parts order.
Yes the adjuster brackets should work for 60k miles like they originally did. They don't. Sucks, but whaddaya gonna do, complain?
Under this maintenance and adjustment scheme, even the brackets cracked behind the a/c p/s mess generally keep working in their squeaky way of working without fail.
Face it, we drive Volvos, not something you can order a kit from "March" to convert to serpentine belts. It ain't fair, but no 1/8" of magic bushing material cures what ails us.
Hate to throw water on the idea of a better mousetrap than living with mice, but dammit that's how it seems from here.