The only way I can think of is copying the directory structure from another OneClick server (if you have more than 1).
You should never edit the original files. You should be copying the files into the $SPECROOT/custom directory and then those 'override' the built in ones.
If you haven't got a secondary server or backups to use for restoring the files - you would need to upgrade (since this replaces files not in custom) or install over the existing version.
Make sure you backup your existing spectrum directory before doing this as some files are overwritten and some of your other changes might be overwritten too.