The assembly drawing I am working on contains a sub-assembly that someone else has dissoved in the BOM.  I want to restore it so that insteqad of showing all the parts and pieces, that it will again show the sub-assembly no.  As I look in help, it says that I should be able to right click a modified item in the assembly structure column of the BOM and select Restore Restructured Components.  Nowhere do I see a Restore command.  Can anyone help?  Thank you.