DFrame Collision Detection

I’m working on a grid-style inventory but have run into the problem of my weapons being able to overlap eachother and occupy the same slots. What should/can I do in order to detect whether another weapon is already in the slot or not?

Just to clear any confusion, I’m not actually using DFrames for my weapons. I’m just assuming that if it works for DFrame, it can be done on others.

You should probably have a boolean for the slot and if it is occupied, do whatever you want it to do.