How do I restore from the backup zip created during confluence upgrade?

[Yoshi Okamoto]

I was on Confluence 6.15.4. I went to install 7.8.3. That didn't work, and I assume it was due to my using an internal database. I uninstalled 7.8.3 and instead installed 7.4. Now I am struggling to restore the site on 7.4.

From what I can tell, two zips were created during the upgrade install process. One was in the c:/Program Files/Atlassian folder. Looking at it, I think this is the installation of 6.14.4. A second zip was created in c:/Program Files/Atlassian/Application Data. Neither of these look like a backup zip, and now I am lost. 

Tomorrow, I think I will attempt to reinstall 6.15.4 and then just extract and replace the Confluence folder in Application Data, but honestly I am grasping at straws. How do I restore from the zips created during the 7.8.3 upgrade/install?