Change tray icon for a specific application and plasmoid

[pemartins]

How can I change the tray icon for a specific application and for a specific plasmoid? I tried changing some things but I had no luck.

I'd like to change the tray icons of:
application: alarm-clock-applet
plasmoid: org.kde.plasma.notes

Everything I use but these have monochrome icons in the icon sets I use.