How to Setup a Place of Supply Rule Type for Sales Transactions

Hi,

I am implementing tax for a UK Operating Unit

The Default value for the 'Place of Supply' Rule Type is Ship From so I don't need to setup any rule for Purchase Transactions because wiht the default always will look at the Ship From from the supplier that is the country associated to the address linked to the Supplier Site.

For Customers I want to determine the 'Place of Supply' from the 'Ship To' or 'Bill To' that is the customer 'address'.

How I need to setup this rule?

I want to say that whatever the country is it should look at the Ship to (or Bill to) is ship to is not available in the transaction to determine the POS for Sales Transactions.