Label your boolean indicators, hide them after if you like. Right click on the indicator in the cluster you want to be able to disable(from the controls panel), select: Create attribute node (LabVIEW 5) or Property Node(LabVIEW 6). Go to the diagram window, right click on the Attribute node and select "Disable" (LabVIEW 5), or Property Node and select "Properties", then "Disable" for Property Node.
Note that if you make a copy of the cluster that has same named controls/indicators, the Attribute/Property Nodes will have same Labels, which can cause confusion. NI would be helpful if they implemented a dot notation to distinguish which Property Nodes came from the appropriate cluster. Hope this helps.
