[Kwant] Changing color limits with kwant.plotter.plot

Dear kwant community, Is there any way to change the color limits in kwant.plotter.plot? I use the site_color in kwant.plotter.plot to map my data on a 3D system. In contrast to kwant.plotter.map, there is no vmin/vmax option. I know that I can assign the figure to a subplot with ax. But I haven't found a way to create a colorbar or set the color limits with this option, because I lack a mappable. Has anyone figured out how to do this? (or if it is possible) Thanks, Jannis