I've just made some mods to my cooling system as although working, it seemed a little hot. May be worth taking a look for ideas.
https://flic.kr/p/Fy1ryz
It's still hovering around the 95-100C mark but better than before. I'm also not sure how well my gauge is calibrated. It's matched to the sender so I'd expected it to be accurate. I suppose my thermostat could be sticky or the pump dodgy though it is a metal impeller one so should be good.
Nigel, what temps do you see as you have an identical engine to me, and very similar rad, though possibly different routing of pipe work.