Thanks, guys, great input.
If you're uploading a sim here, it is probably enough to post a picture of the Clean pack installer window. If the creator never named the file anything sensible, then (in my opinion) it is that person's fault.
Just remember that the first file showing up in Clean Installer (a string of numbers) is usually the sim itself
Oops! I was using the Clean pack to clean up a file and I was taking out the unidentified "string" - so that's why I can't find them!?!
