I've actually started a set of letters. Of course, it will take a longer bridge to put "Norfolk and Western Railway" on the side of, but rather than getting burdened down in a bunch or road names, I'll do the individual letters. Besides, with the way a spline stretches to some degree, what logo fits on one bridge won't look right on another with the bracing of the girders poking through. This way, each letter can be in its own pocket on the bridge.Here's a very rough example- I only made 2 letters, I'm not happy with the font, and haven't weathered them out or anything yet. This is more just to get an idea of how it will look and to get some ideas about it:
Anyhow, I've got a little tweaking to do with it. And I made the original one two sided now, so you can put a logo on each side of the bridge. Can't do it with the letters though, because one side of the bridge will say CONRAIL while the other will say LIARNOC. That's no fun.