I had to wait a fair while for the paint to dry (and it isn’t really properly hardened off yet), but that wasn’t a major issue as I was also waiting for some stainless screws to arrive. Yesterday I finally got around to assembling all the parts so far and this is how it now looks.
I have a couple more sections of 30mm square timber to fix across the back on the inside to allow me to fix the sensors in position, but the major piece left to do is to fit the upper roof. That has all been painted with undercoat and hopefully this week I can get the final coats on so it can be completely assembled and put into place next weekend.