I won't bore you with another "how-to" as there are plenty of people on here already who know what they are doing. But - Personally i superglued with 1 or 2 tiny drops the gasket to the sump pan and then carefully re-fitted it making sure as i positioned it the gasket still protruded slightly all the way around and didn't do it up overly tight!

Its a nightmare job - good old Henry Ford eh lol!

Good luck!