Tool Size?

[huzilulu]

I am building up my tool set for the upcoming build, and had a quick question:

1) What is the thickness of the ally panels? I am looking at a couple different air nibblers, and they have different applications: some only upto 12 gauge, while others are 16 gauge.. How thick is the ally, and what kind of nibbler will work well?

2) What are the sizes for the countersunk bits that will be needed?

Thanks

[huzilulu]

Thanks everyone!!