UMG Inventory Tutorial Help

So I followed this great UMG Inventory Tutorial so I can have an inventory in the game I’m working on. My only problem though, is that he didn’t show how to stack items and I can’t seem to figure it out for the life of me. The other inventory stacking tutorials are so different from the one I did that I worry about (and can’t) implement their methods into my project. I know it is a bit of a long shot, but I’d really appreciate it if anyone can help me figure this out.

The only major difference between my project and his tutorial is that I pick up items through collisions instead of through a key press.

scan inventory array with a for each loop if the item equals new item get item quantity of inventory item, add new items quantity coming in, set array element from inventory array, get index of inventory item from for each loop index.