Tagging shaft base level by project base level

[eyalbRAPVR]

I am trying to find a way to tag the base level height of shafts in plan views. (Revit 2024). I cannot use plan region as it ends up displaying all elements from levels below even if I define a very small region inside the shaft boundaries. I tried tagging the room that defines that shaft but could not find a way to display it's base level. The lable of it only allows for display the base level by name and not its height relative to the project base point. 

Any ideas?

Thanks

[vitorbortoncello]

maybe a model line woul help