Yes Kev , it was a good year ago last time i had the sump off so it's been a while.
I am sure the sump is still well sealed with the gasket.
When i last had the sump off, i used the socket attachment for drill use and done a few of the threads on the sump bolts. i assumed this was how i was losing the oil.
Will have to get the sump off completely soon to helicoil these damaged threads . As i don't think you can do that with the sump still on.
A few days ago i was doing exhaust rubbers and notice the pool of oil on the ground was quite big. It had gradually been getting bigger over a few weeks. when i investigated i found the missing bolt was the cause.
There was only small dribbles on the ground outside the house at first, but were getting bigger so i had to get into action
Another little problem fixed for now.
Funny thing with the diagram is the long bolt is obvious if you look carefully. And even the haynes manual tells you it's a long bolt.
Just too hasty at times.