I have a rip in my liner and I will have to replace it with new liner. Pool is inground 20x40. Pool was constructed in 2010 and we bought house 4 years ago. I have the company where the original owners purchased pool and they have all the dimensions from original pool size ans dimensions. Is it safe to just reorder the liner for the pool based on the original pool?? Do we still need to measure or can we just go with the original specs?