Product review (5 stars): Easy fix. You might try contacting Whirlpool to see ...
This cured the problem of water dripping out of the bottom of the freezer section of my KitchenAid refrigerator. Somewhere on the web you can find the service bulletin and the list of refrigerators needing this piece. I took off the lower back cover using a hand-held nut driver (1/4 inch?). You could also use a small adjustable wrench.  I pulled off the old pieces (duckbill and tube) and tossed them in the trash. I then poured hot water into the slots in the back of the inside of the freezer compartment. This was to flush out any items in the pathway and prove the pathway was not obstructed. Water did flow through and filled the drain pan near the bottom in the back of the refrigerator. I sponged out the water in the drain pan. Next I snapped in the new extension piece and screwed on the back cover of the refrigerator.  Easy fix. You might try contacting Whirlpool to see if you can get the piece (and installation) for free. I didn't want to go through the hassle and bought one here for my two-year old refrigerator.