OpenXML.WordProcessingML document processing (HOW TO XML correctly?)

[sao123]

I have read a word (XML based) document into a WordProcessingML document object.

Very generically is has the form

<w:p>
  <w:r>
    <w:t>This makes a very very very wordy and deliberately overcomplicated sentence.</w:t>
  </w:r>
</w:p>

it wordwraps and breaks at the wrong place...What I need to do is insert a NonBreakingHyphen into the text sentence.
The resulting document should resemble this:

<w:p>
  <w:r>
    <w:t>This makes a very very very wordy and deliberately over</w:t>
<w:nonBreakHyphen/>
<w:t>complicated sentence.</w:t>
  </w:r>
</w:p>

How do I break a
DocumentFormat.OpenXml.Wordprocessing.Text object into 2 seperate objects, and then insert a DocumentFormat.OpenXml.Wordprocessing.NoBreakHyphen into the parent run at the correct place?

I'm not very good at editing XML in using the SDK.