Mass EPS assignment in XML import

I have a P6 XML file that I want to import into a new database. Using the P6 Client is not an option.  The problem I am having is that the XML contains a minimum of 500 projects that I will need to manually assign an EPS before I can import the file. I'm wondering if there is a way to edit the XML file so that I can populate it with the intended EPS.

I thought maybe if I edited the value in each <ParentEPSObjectId>VALUE<ParentEPSObjectId> in the XML file to match a single project I exported from the new DB, but that did not work.