Custom KDE wallpaper

Hello, I've been attempting to change the default kali linux wallpaper that is over-layed during my build of a custom KDE image. Ive attempted everything from placing my renamed "kali-wallpaper_1920x1080.png" custom background in the "config/includes.chroot/usr/share/wallpapers/kali/contents/images" and "kali-config/includes.chroot/usr/share/wallpapers/kali/contents/images" directories, to changing and overlaying the desktop-background.xml file, but nothing works.

I have been able to successfully use my own wallpaper in builds using, lxde, xfce and mate, but not KDE.
I have watched and read every tutorial by the Kali Linux team and combed through the web looking for an answer but I cant find anything.

My question is, has anyone successfully managed to build a kali KDE iso using live-build with a custom wallpaper? and if so how did you do it?

any help is much appreciated!