Started the day by repositioning the rear light clusters. It was really bugging me that I'd made such a basic error. As the old adage goes, measure twice cut once. I ended up measuring three times and cutting twice.
Lights successfully positioned, I started to wire in the nearside cluster. This was quite simple and only confusing when I had to find the nearest earth point, which turned out to be the fog lamp connection. This effectively is the earth for the rear loom.

I fitted the tadpole trim around the rear arches. It fitted OK, but I wasn't entirely happy with it. I took a couple of photos to show the difference with or without.

By the time it was threatening to rain I made up my mind and took it all off again. It will need a line of sealant run along the join but I think it does look neater without it. Maybe it looks better when the body is the same colour as the wings? I don't plan to paint the car body anyway.
Now sitting typing this as I decide whether it will rain or not :-/