All old vehicles have oil leaks - mine more than most. But generally I don't mind that on the bikes but the Dub is dropping on the drive and it needs sorting. So while I have the drive shaft off I might as well try to change the gearbox oil seal that is weeping.
So, I removed the centre cap and circlip from the gearbox outlet shaft and the drive flange should just come off. But it didn't. So some light persuasion with a chisel and some Moleys got it off eventually.
Revealing the offending seal:-
Gotta pull it out and replace but that for next time.