[eluser]TheFuzzy0ne[/eluser]
As far as I know, it has to be done across the board, and it's the index file that must be queried.
To do this, you need to enable query strings in your config.php and perhaps change the URI protocol to query string.
If you want to put a question mark after the controller name, then you will probably have to allow the '?' character, and set up some routes (don't forget to escape the question mark in your routes).
