I have a 2005 exmark 60 inch deck. I kept slipping the mule belt under the double jackshaft pulley and finally realized the lower lip of it has a ding that bends down. Sometimes when I engage the blades or hit some tuff grass the belt slips and gets stuck. Is this a tuff fix and I am I better replacing the whole assembly or just the pulley itself? Any tips would be great. Thanks and safe mowing.