I use WordPress 3.7.1 and Contact Form 7 3.6.
I would move the box green with confirm message under the module contact, because if the module is long the user doesn't see the confirm message.
I was able to get it in a old version of this plugin, but now i believe that it is different.
I opened include\classes.php and i found the form_response_output function and now? What i do?
Another question: can I make this final modification so as not to be overwritten by subsequent updates of the plugin?