In Operations Manager 2007 R2 there is a new view in the auhtoring workspace called Overrides. You can use the override view to edit/view/add overrides. You can also use it to show what overrides you have in which management pack. Click on the Override view and then right-click in the result pane, select personalize view, then select to group items by Override Management Pack. That will give you a list of all overrides, groups by the management pack that stores the override.