Hey thanks for the input guys. The pulley is pretty well shimmed at the moment. By float do you mean allowing for some transaxle play?
It sounds like eyeballing is the established practice. Just have someone rev it on the stand and look down the belt from the front of the bike to make sure the belt is straight at full vario?
Side note: the cardboard trick is neat but holy smokes do those fly off fast and somehow always directly at my face