Not quite sure if you will be able to remove it without tearing down the system, but you could try it.
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Ok, looks like I will take the sides off and give it a go. I do remeber another post regarding the same piece but can't find it. They said something about only four pins holding it on. I'll post after I try it. Thanks to both of you for your help.
Ok, problem solved. If you remove the right side panel (only one screw holding it) and then remove four very small screws (2 on each side) you can remove the mesh top. This will allow people who want to secure a fan easier access to the metel mesh frame for securing the fan.