Upload Primary Content from External Location

Hello,

We have a requirement where we would like to leverage a Sharepoint location for a Document and in Windchill create a template with Sharepoint location with like an excel file, Now what we want is, when New Document is being created in Windchill, The Primary content of the new document would be the excel file pulled directly from the SP Site, The intent is that some templates that are managed outside of Windchill wouldn't have to be managed multiple places, Any help is appreciated. Please recommend a non Customization approach.