Half Wall Trim Height Restriction

I'm currently trying to create a way to remove the half wall trims in a way that means light still affects the top of them correctly.

I have removed the trim itself but the top of the wall that is exposed is only affected by outdoor lighting so I wanted to add a cap which I can create in a few different swatches that will correctly light up with internal or external lighting.

I have a package that works (two packages technically that work together, the trim and the fence) but the game won't allow me to place it on the three tallest half walls for any given full wall height. It complains that there is not enough room for the "partition."

I've been hunting to no avail to see if there is a setting somewhere within either the trim or fence resources that flags how much space it takes up. I'm starting to think that simply having a fence attached to the trim disables these three heights and that it cannot be edited but I wanted to come here to ask in case anybody here has a better understanding of the file contents.

The three existing EA trims with top attachments all work this way even though one of them is actually short enough to go one wall height taller.

I've uploaded my files to OneDrive for anybody to take a look at> 1drv.ms/u/s!Am8KXkA0MW12lDvbPYJZ3OhZQsma?e=yZo3kp You'll need both in your game for it to show up correctly.

Thanks.