A Harley forum suggested more belt tension than the standard 5/8" deflection with a 10lbs load, I tried it and it was worse. Slightly less tension and the squeaking was gone, so that may be the way to go, along with a nice clean belt and gear wheels.
This seems to indicate that belt tension may be the cause rather than alignment.
Planenut, how much did you slacken off the belt to stop the squeaking?
