When I started to put on the roof, it got too dark inside to see any of my interior details.
While I don't really do night scenes, I decided to light the interior just enough to be able to see in. But first I had to order some LEDs.
While waiting, I decided to baffle the roof edges. My roof fit-lines are pretty good, but nothing ruins a building like light leaking out at the joints. The baffles are spare strip wood, painted black, and spaced back a couple of mm from where the walls will be.
I used a surface mount LED because there's not a lot of roof-space in the depot, and I want the light to spread out as much as possible.
I installed a diffuser to further spread the light. After trying wax paper, typing paper, milk jug plastic and tissue paper, I settled on tissue paper (as in model airplanes, not Kleenex). The diffuser is glued to the roof at the front, and to a stiffener at the back to keep it from sagging into the interior.
Cheers,
Jeff.