I did 60 kms this afternoon over some rocky terrain and no movement, so far, so good.
I've thought about this a bit more and it may actually be best to sleeve the shaft for the bottom bearing and use the Suzi bearing there, and use the KTM bearing on the top as per above. The advantage of this is that the Suzi bearing is slightly bigger, so presumably can handle more punishment, and the cup would be fully supported as per standard, whereas what I have done means the cup is not quite as fully supported in the headstock. Not much in it, but might just be a better solution.
I should do a 1000 kms or so over the next couple of days, time, and kms, will tell.
EDIT I've done this, see post 206 by scrolling down here: