Database files are like Word files, they are normally saved in the User's Document Folder. Search for *.fp7
BUT, they can be Saved anywhere.
If the files open in FMP 8.5, use Save As to determine where they are. Backing up files is very important. I would only convert a copy of the 8.5 database and Save As Smaller AND Save As Clone would be a good idea. Convert the Save As Smaller and test the file.
Thank you so much for the help. Didn't realize I could just copy the file icon.