I'm looking for a resource to get all the ecu four digit ecu codes for the Focus over the years.

Its the ecu identification code, not fault codes.

I've found a Mondeo list but can't find much on the Focus despite it using the zetec engine four years longer than the Mondeo.

http://www.projectbobcat.com/guides-mondeo-ecu

Are you still looking for this data?
Jason.