Put a box on top of another

I need to put a dragable box on top of others that are pawnned in game but I can’t get this thing done. Someone please help. I’m stuck with this for weeks now and everything I tried doesn’t work.
I used this tutorial to make the dragable box

Now I just need some way to put the box on top of others. Please help.
Contact me via skype if possible
eder.hsoliveira@outlook.com
Or put some BP examples