its very hard to say for sure where they will end up at. I know that might be hard to understand, but untill you have the pool together then you will. the pool flex's alot, and with the flex the legs move. mine is pretty level, I think Im off 1" and that was from using a string level, get a laser level to level it up. you can find cheap one's on ebay for around $25. back to the legs, I did the same as you and wanted to set them on pads and did but after filling they slid almost all the way off in places, I used the 6x12 pads, so if I was doing it again, I would use the 12x12 pads and hope when the pool filled the legs would still be on the pads. to me that your best shot, some of my legs or stright, some lean a little in, some lean a little out, and if your standing on the outside of the pool when everybody is jumping and playing it will scare you to death how much this pool moves around, don't get me wrong. its been an awesome pool, I upgraded the filter to a sand dollar 1hp sand filter, which was the best thing I done, we are in our second year with this pool, next year we are going to upgrade to a 24'hardside above ground,
If I can help in anyway, let me know