I don't know httrack well enough to give an answer in regards to it but after
the mirroring is finished I would remove the unwanted text,

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with a text replace program such as this one for Windows:

<http://www.ecobyte.com/replacetext/> - kind of steep learning curve. Noted
caution to Windows 7 users on website.

For Linux users sure to be something to do the same thing.