Glenn - I need a bit more information on how to do this. One thing that makes your posting difficult to understand is that the URL is shortened so I can't see exactly what you did. And when I click on it, the exclude function is used, but the URL that appears in my browser is not what you had, but a search URL.
Also, what identifies the different sub-forums? It appears that you're using numbers. How do I know what numbers apply to which sub-forum?
While I have questions, I really appreciate you posting that technique. Thanks!!
Go into the world and do well. But more importantly, go into the world and do good.