Yeah I think I just needed some further tightening.I used the gasket the way Hayward said and have no leaks after 3 years.
The gasket seals against the back of the liner and it works fine.
I’m up and running. Have had the pump on high for about 6 hours now. Going to keep it on high for at least 24 hours then probably switch it to low.
I have the timer set to manual (always on for now), what’s best practice for a 24’ round by 52” above ground pool? 1.5hp pump.