If you where trying to add specific new variables into the existing menubar plugin locations could be added to achieve that at specific locations.
Although a quick and dirty plugin based on the global plugin location might work as $menu and $menu2 are defined variables passed to the functions in the program. You might need to add a · here or there but say this would work to place a link on the left menu.
Content visible to verified customers only.
You could expand from there.