As I had mentioned in this topic: https://www.v11lemans.com/forums/index.php?showtopic=20337&hl= my gearbox had cracked, probably due to dropping the bike once. As suggested in the topic by a bunch of you guys, I felt adding the brace with the new gearbox from Rolf was the way to go.
Last week I finally found the time! Some pics:
Making a cartboard tryout.
Steel insert ready for welding.
Welded and paint restored. Not the greatest paint job I know, but once the bike was put together you could not see it anymore:).
Connecting plate painted in the right colour.
Let's hope she never has to hold anymore (as in: I don't ever drop her anymore), but if I do, that this will be sufficient in order to protect the gearbox!