Use a round over router bit to round over these stiffeners BEFORE you install the galley flat. It was impossible to get to the ends of the two outside most stiffeners due to interference from other bits of the camper.
Do it at this step. Not after installation:
Also, use lots of physics and computer science books to hold everything together while the epoxy sets up. I made little pencil marks at each end to line up with the holes drilled into the flat. The bars did shift slightly, but it was rather easy to push them back where they should go once the epoxy is on them.