See photo to see the new build area with purifiers I put down as an example.

All scrappable items outside of original build area are now scrappable. Increases build area. Increases NPC sandbox. No objects or terrain touched. No enemy spawn markers inside build area.

Simple mod. Stretches the build area all the way up to the water. That pool ain't enough! New area is around that diner and bus to the water. The other corner remains the same. See photo. Note that the diner, bus, and weird umbrella platform are not scrappable.

This is how the settlement should have been made. 

If you're wondering why some objects are highlightable but not scrappable its because there are mods that make extra things scrappable. I added these to be 'potentially' scrappable in case you have those mods installed.