LEFT: Carefully remove the squirrel cage from the old motor shaft.  Check the cage and look for broken or split areas.  If you find any areas that are damaged in the squirrel cage, replace it.  Zips will be able to help you get a new one.  Also, remove the ground wire clip.  Make a note of its position on the motor housing flange.  You will have to re-install it onto the new motor housing flange later.  You should also remove and clean the blower motor rubber duct.