You may want to shoot me for saying this, but now that you've painted the roof white, I think your bus would look better if you lowered the rain gutter on the raised section of the bus to be on the same plane as the gutters on the front and rear non-raised sections, then smooth out the line where the original rain gutter was to blend it in, and then continue the white paint down to the level of the new rain gutter.
It might pan out like this:
- cut off the raised section gutter and smooth out the transition line
- have a metal shop make you a new gutter the correct length to connect the front and rear sections
- Install the new gutter and then re-paint to cover the areas you modified
It would be extra work, but I think it would look awesome!
Maybe someone could use a photo editing program to render what it would look like. I don't have a program handy right now that would do it justice.