Applying insulated rail joiners using Kato N Scale

[SVJ_Nscale]

I am looking for a way to indicate where I will be placing insulated rail joiners. I am modeling in N scale using Kato Unitrack. Is there any way to do this other that coloring the sections of track for each power feed and adding text next to the rail section?

[Shinkansen]

I was trying to achieve this as well, thought of a coloring workaround, but it would be nice to have a way of marking selected element boundaries.