I noticed on your website that the white plastic washer that goes between the foam wiper and the retaining pin is not used on the old style 880. I am trying to rebuild mine and the foam wiper has disintegrated over the years but I also don’t have the white plastic washer. Before I rebuild I don’t understand why the white washer is not needed. It seems like having the foam wiper against the roll pin would cause the foam wiper to wear prematurely. I am understanding this correctly?