Swapping out the bottom case

Mates,

I'm using the step-by-step guide to swap out the bottom case on a macbook pro this weekend. The guide states that one of the tools required is a "4mm nut driver."

However - nowhere in the guide can I find the step where this tool is used. I don't have this tool, and can't get it in time for this weekend...

Has anyone else followed this guide? Do you know which step it is required in? Do I really need to have the "nut driver" for this project?

Thanks for all your help.

Armen