I talked to a guy today who has already jack hammered out his old skimmer on a 20x40 concrete inground. He was planning on sliding the new one in and siliconing it to the old concrete. I dont do a lot of work on concrete/gunite pools. What is the proper method of replacement? Do you need to cut the concrete out to a certain size larger than the new skimmer, form the wall, and pour? Should you try and keep the hole tight and do a wet pour? What is the correct type of concrete to use? Do you paint afterwords? I would guess that you should also hammer drill and epoxy rebar stakes into the exising wall to prevent shifting. Any help would be great.