Guess that's buggered up your dad huddie, I thought this may have been an outcome on the other similar issue, (who was that??),
Makes me think that the Wet-sump issue is not so bad after all, makes for looking in places we would usually pretend don't exist- a bit of an engine saver??
Maybe BSA designed it in as a safety factor and should have a part #..?
Good luck with it !
Cheers