Specifying a different fax context

What I am trying to do is specify a different context for receiving a fax. The first thing I did was create a custom destination “faxserver-rx,s,1” under ‘Tools’. Now I want to specify that all inbound faxes use that context instead of the default “ext-fax”. However, the only thing I see is that you can specify a fax extension under ‘inbound routes’. Any insight at all would be greatly appreciated.