That can't be done.
My model isn't a single file, it's a collection of about 2500 files carefully shaped and positioned. This isn't on sketchup either...
Adding elevation won't alter the look all that much, but it would add a good sense of depth behind the towers where there are hills and valleys. Creating the terrain would be easy, but re-positioning all those buldings, (about 1200 or so) let's just say I'm not looking forward to that...
Here is the view Porter pilots coming into the Island Airport must be used to:
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