I'm planing on installing a new vinyl liner this weekend. The steel walls around the skimmer opening are quite rusty. Now I'm wondering what the best way to seal around this opening is? First of all the inner gasket for the faceplate will be sitting on rusty metal, which is not a good precondition for a reliable seal. Secondly, the sides of the wall (along the wall thickness) would still be exposed to the water. One could try to wrap the liner around the wall when making the cutout? Would it help to use silicone to seal and also use it between the inner gasket and the steel wall? Any comments, ideas are appreciated.