The fix is pretty straight-forward, have done it four times now. The Whirlpool design/product is the problem. I keep a replacement in stock, this was the replacement for that back-stock I just installed. I would suggest not buying Whirlpool but, if your looking at this, it's too late.
Time to fix is not a straight forward answer. The actual replacement takes about 15 minutes but thawing out the ice-mess created by the poor design takes more time.