I am installing RV hookups at my 'hideout'.......myself. I am using a plastic Septic tank and the Chamber type lateral. Have watched a lot of Youtube stuff but have never seen anything as to the height of pipe entering and leaving the tank ( same height or is the exit slighly lower than the inlet ?). I will be using 4" PVC 'Ys" as baffles inside the tank but have never seen anything as to how far down inside the tank to put the verticle portion of the baffle.