If you have to change stuff in the platform files manually, it’s not a very good plugin.
Look at other plugins to find examples of how to do this. I think Analytics plugins are good examples as they also tend to be started with the application.
That would be the best solution - forking the plugin you linked to and make it do these things the right way.
The more practical solution is probably just do it “the dirty way” and be aware that your changes in /platform can be lost or overwritten quite easily. (I just create a git repositor in there and commit to a remote repo for safe keeping)