If one wants to use a template from the Site Library on a site with existing content, would this workflow work?
1. Back up the site, including the wp-content folder. And use Tools – Export to export the content.
2. Create a staging site.
3. Delete all the content so it seems like a fresh new site.
4. Import the desired template.
5. Edit template as desired.
6. Import content with Tools – Import content.