How to Setup a tax zone for European Union!

Hi to all,

I have a problem while I am implementing EBTax.

With domestic customers-suppliers tax is been calculated automatically.

But that is not the case for foreign ones.

Implementation is in Greece.

So, the tax regime has geography name Greece

Questions:

1) before i create a tax zone for the EU countries must I define geography structure for all of them and manage validations where I must add to the fields county, city the locations and check the boxes tax validation?

2) when i will create the tax zone in code type I choose FIPS Code or TAx geography code?

3) then after the creation of the tax zone i insert it when I will create the tax on geography type or i will leave it greece and put it in tax jurisdiction field?