Yeah most work shop manuals say wrap string around it etc etc.
Don't worry to much. most of the drag is the seal anyway.
Just very slowly nip the pinion nut up and check it by hand. It's not to different to a front wheel bearing on your ute.
Try dummy assembling it with out the seal and crush tube in it, set the bearing so it's tight but not notchy, mark the position of the nut on the pinion, take it apart assemble it finaly and adjust the nut untill your marks line up again.
Think of it like adjusting a wheel bearing. It needs to be tight but not to tight.