Rewriting elements and attributes with dataprocessor

So how would i rewrite an element's tag?

I don't want to learn regex to replace html elements.

The best example i've found is the placeholder, but it uses regex to replace text ..

I have some custom elements that look like this:
<idt:templatefield contenteditable="false" error="" expression="((INNOMATE.Base.Employee)((INNOMATE.Data.Serialization.MappedObjectReference)activity0.Arguments[&quot;bdcc4f8c-3dc1-4d94-9cc1-a9892dacfd46&quot;]).GetRealObject()).FirstName" isformattable="false" label="Medarbejder → First name" longlabel="MUS 2011 → Medarbejder → First name" style="background-color: #ffff00;" type="String" xmlns:idt="http://www.innomate.com/Diesel"></idt:templatefield>

i can catch them with this in datafilter:

    elements:
    {
       'idt:templatefield': function (element) {
          if (element.attributes && element.attributes['label'])
          {
             // tried alot of different things here, but no luck so far..
             element.attributes['style'] = templateBGcss;
             element.attributes['contenteditable'] = 'false';
             element.innerHTML = element.attributes['label'];
             return element;
             //return CKEDITOR.plugins.placeholder.addFieldFromExisting(editor, element);
          }
       },
    }

But how do i rewrite the tag name? ..or copy the attributes to a new tagname?

I want to use the label="Medarbejder → First name" attribute as the name for my placeholder.. so it would look something like what the placeholder plugin does. (sorry, can't use bg color here )

[[Medarbejder → First name]]

I'm confused by the inconsistent JSON usage.. and the CKEDITOR.dom.element documentation lists alot of methods that arent allowed on this particular element ..

I can't use .setText() or .setHtml() or .setAttributes() ..

Help!