I put the jack under the engine right next to the drain plug so I had to take the cover off and let the oil drain from there. More than 4 litres of oil came out. That's a lesson for next time if there is one!
The cover, o ring and case bore had traces of some type of sealant. I used a plastic trim spatula and finger nails to remove it all. I was careful not to drop any in the opening at the base of the bore.
The case halves are not perfectly level at the case join but not that bad. Equally the cover appears straight.
