Happy job finished update:
It took two attempts to get the ribbon cable to seat properly. Otherwise not
too bad I guess. Took about three hours in total. Drilling the holes to access the screws holding the LCD unit in place was a bit worrying when you're just guessing based on someone else's photo !
I also fitted some "satin chrome" rings while I was in there, although they're just silver paint rather than satin chrome. Not 100% sure I like them, but I don't dislike them enough to take them out again.
Anyway, I'm glad I've fixed the LCD. It's one more thing off the list.