Grid Based Inventory Need Help!

So i'm creating a game and want to do a Grid Based Inventory, i've gotten the normal inventory down, EX: every item is a 1x1 slot, and every slot has a 10 spacing in bewteen and such. I want to make it so items like a pump action for example take up 2 by 3 slots. How would i got about making this?

 

This is not the correct place to ask this question.

This forum is for discussions on or presentations of learning material.

I would suggest one of the other forum or support threads.

FWIW: A simple google:
https://www.google.co.uk/search?q=u...69i64j69i60.9447j0j4&sourceid=chrome&ie=UTF-8

Gives many results:
http://answers.unity3d.com/questions/787882/grid-inventory-multislot.html
https://forum.unity3d.com/threads/grid-based-inventory-system.81242/
http://answers.unity3d.com/questions/1330809/grid-inventory-move-item-slot-highlighting.html