Sorry for late response I hope you are still around, it depends what leak you are using, I can garauntee my leaks are 100% clean without a note of being nulled however if you want to do this its quite complicated you need to find origin of all files for instance I use C9 it searches between files and inside of files for words
so if I search for nulled it will show me which files has these words and you can then remove them.