Book off half a day to start. Remove everything you can (hoses, curtain, water distribution tube, float and clean separately. Run a sanitizing cycle then clean out the dispenser of ice and rinse thoroughly. Make sure the hoses are clear as they block up. There is a restrictor to remove from the hose by the distribution tube. There is often gobs of bacteria around and under the evaporator which you can brush out sort of. You may have to snake the dispenser drain as the guck from above can block the drains. Good luck Mr. Phelps.