Widget Blueprint Replacement

Basically, I have a widget blueprint that is is a mess. So I have created a new version, which has a new name.

The old widget is referenced by a load of blueprints; the new widget by nothing. I want to transfer all the old references to the new widget, but I can’t find anyway to do this in the editor. If I delete the old version before renaming the new, I lose all the references and have to hunt them all down manually: which is a pain.

This is actually a general problem for all blueprints. Is there a way of doing this? Thanks.