Hello I have an above ground pool with Hayward Sand Filter. Noticed sand was getting in the pool and had a broken center lateral pipe so I'm trying to replace the entire assembly. I got all the sand out and drained the tank, ready to put the new lateral assembly back in but for some reason I cannot get it to sit straight. I've stopped, emptied the sand again, drained it and started over multiple times but for the life of me cannot get these things to sit straight. I've filled the tank halfway with water first, put the assembly in, pushed down the laterals but it keeps getting crooked. Any tips or help how to do this? Thanks