I followed the wires to the space under the rear seat and disconnected the connector block:
A quick check of the parts fiche showed that this bulb holder and wiring cannot be purchased on its own, instead Kawasaki sell the whole stalk with indicators and plate holder and everything as a single unit! Most bemused I had a search on ebay, thankfully the same seller who sold me the forks and radiator had such a stalk also for sale. I wonder what he thinks of me.. Anyway, I guess the one upside to this is that it was easier to swap the whole thing than faff about threading the wires properly?
If only it really was easy. The stalk is connected to the frame by four allen headed cap bolts. These get sprayed by the rear wheel because the rear mudguard is a joke, and so they corrode into place. Lots of fun (hammering) was required to free them.
Can you guess which one is my old one?
Bonus round! I found the pin holding the left pillion peg in place had disappeared and the peg was about to fall out, so I used a nut and bolt instead.