Looking at a Mesh safety cover (Meyco, pooltux, looploc or gli promesh). I have a standard 18x36 pool with 2” radius corners. I have center steps that measure 41” x 86” outside edge to outside edge. Do I need a cover with 4x6 or 4x8 step? The 4x6 says it is 4x8 and the 4x8 says it is 4x10...