....they could tell you exactly how they're painted.
Unfortunately, I can't, on account of being hundreds of miles away on the occasion when the Artistic Director arrived with his brushes and pots of acrylic paint to finish off the walls lining the road near the 'Bridge To Nowhere'.
The results are most certainly up to his usual standard..
Lying in the road you can just make out the height warning triangle signs which are about to be installed on the bridge.
Thanks to the wonders of modern home computing it was a relatively simple task to scan an image of a sign with the correct bridge dimensions, re-size it and then print out a miniature version (twice) to mount on the model.
By the way, you can read a little more about Francis' technique with acrylics in this post.