As mentioned above, you do have to remove the inner primary, and pull the axle out of the rear wheel so the old belt can come off, and the new one back on. Then it is just a question of reassembly.
As a note, I would be cautious about using an impact wrench on the compensator nut. Some indication that such use on the pressed crank can have a deleterious effect. Also, it can jar the magnets in the rotor.
TQ