Does anyone have experience of deinstalling AQ and removing the queue objects from the SYSTEM tablespace?

I have recently started working with a production DB where AQ had previously been installed with the objects in the SYSTEM tablespace. I would now like to deinstall AQ and get rid of the unnecessary objects.

I have already had a look in the App Developer documentation for 8.1.6 but could not find anything that would help...any advice on how to approach this would be appreciated!