In my opinion, structural owns the grids and architectural owns the levels -- meaning they are the party responsible for making any project-wide changes to those important aspects of the design.
In the Structural and MEP models, we can see...
the levels in our model and the linked-in architectural model. Plus, we also see their grids they created using the Copy/Monitor feature.
First, lets get rid of the duplicate grids. It is best to do this via your View Templates, as they will update all views, plus any future views created. The steps below show how to hide the grids from a linked model (this would apply to all links with Copy/Monitored grids). Note, that for step #3 you have to select Custom at the top of the Basics tab before you can do anything on the Annotation Categories tab.
In the image below, we can see the linked grids are now gone. Next we need to move our levels (I am structural or MEP right now) to align vertically with the linked architectural levels.
We do NOT want to use Copy/Monitor like we did in the previous post with grids. Doing so would create another set of levels in our project. You should never have levels stacked at the same elevation, as this leads to lots of problems. Instead, we will use the Monitor command. Doing so will allow you to pick an element in your model and then one in the linked model (levels in this case). Once you have picked all pairs of levels (one in your model and then one in the linked model) you click Finish.
Duplicate levels issue: Here is an old post with an image I shared with Steve Stafford, at Revit OpEd, showing a messy project with several duplicated levels in the same project. And, as David Baldacchino comments, deleting extra levels is bad as everything hosted to that level is deleted without warning! Tip - List of All Levels via Grid Generator Extension. FYI: This tip is outdated as we can know schedule levels.
Now, when you select the level in your project it shows the "monitoring" symbol as shown in the next image. We can also use the same steps listed above to hide the linked levels from the architectural model.
Just like in the previous post, anytime a level is changed or deleted both structural and MEP will get a Coordination Review warning when opening their Revit models. We still have the problem where any new levels added in the architectural model are not noticed.