Getting rid of the ends on walls in the map editor.

I'd like to get rid of the ends of the palisade walls, for a map that I'm making, so it looks like fences instead. This is what it looks like before I save or test the scenario, but this is what it looks like after I save/when I'm playing the scenario. Is there any way to just get rid of the ends? I know you can extend the palisade walls and then use the triggers to get rid of the ends, leaving the middle, but the problem is, I have rock decorations on the ends, and when I use the delete effect with the triggers, it also deletes the rocks. Any other way to do it?