I just got a 21 foot steel AGP after having a 22 ft intex soft side for 6 years that finally died. I getting ready to set up the new steel pool and I know it comes with the skimmer and one oulet hole pre-cut. I want to add another hole for a light and another hole to use on a fountain I added to the pool . So I know how to cut through steel my questions after cutting do I duct tape the edges? My fear that the new holes put tears in the liner. Do I sand them....just looking for someone who has done this to maybe help out. I don't have to do the light as I could just mount it to the steps but I am a bit freaked out about have a power cord in the pool behind the steps. I appreciate any input thanks.