You can access the plastic blower fan wheel from under the dash and through the dropped glove box. Remove the metal clips that hold the plastic tray under the blower ducting. You will see the hex head screws that hold the panel onto the blower box. You must remove or move a few air duct hoses and the blower control module to access all the screws. Once they are out, the panel can be pulled to provide a direct view to the blower wheel and the source of you fan rattle. Probably paper that was drawn into the recirc opening from the glove box.
While you are in there, you should also pull the blower wheel and clean it. You should also clean the evaporator fins of the accumulated dust that is undoubtedly clogging the flow of air through it. I used damp towels and a vacuum cleaner to clean mine just a few months ago. I found a great deal more air flow after the cleaning that was obviously being blocked by the buildup of dust and dirt.
