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We're currently working a project to restructure our current category/subcategory/item list, as the one we have now grew pretty haphazardly and we need to put some organization to it.  Has anyone else done this and can give some pointers?

One issue I see is that we have hardware items set across 5 different categories and we'd like to collapse them into a single Hardware category and then multiple subcategories.  Is there a way to provide a mapping of old to new that can be applied?

Any help at all would be appreciated.  Thanks!