Shoutouts to Mikey (PGSK) for finding this method.

Use a save manager to backup your save. Drop this file into the Sunshine folder of the backup, and then restore it. (You may need to rename the file to "A.sav" no quotations)

If you play 64 or Galaxy, you may want to repeat the process every so often or keep a backup as to not lose those saves (since it replaces all 3).