Product review (4 stars): You are pretty much on your own
Not a whole lot of instruction or help from vendor.  You are pretty much on your own.
I have to pry reasonably hard on the old socket to remove it.  Depending on your refrigerator and age, it could be very scary.  Mine is a Frigidaire Crown, and my light bulb made terrible crackling noise one day, and quit working.  I read about it and purchased this a 1 of 3 troubleshoot options.  When I pry on the old socket, it made crackling noise like it would snap or break, but the socket will come loose eventually.  The little plastic tab near the bulb socket is the locking mechanism.  For least resistant, you should attempt to lift the socket from the back toward the front when prying (behind the bulb socket - lift upward and toward the front/socket opening).
Unfortunately this socket is not the problem for my refrigerator, and replacing it did not solve the problem.