Right here you go.
Don't say I never give you nothing.
You can change the text if you want, but I think it does the job OK.
Bang this right at the bottom of the navbar template
Code:
<table width="100%">
<tbody>
<tr>
<td class="thead" align="center">
<a style="float:$stylevar[right]" href="#top" onclick="return toggle_collapse('announcement')"><img id="collapseimg_announcement" src="$stylevar[imgdir_button]/collapse_thead$vbcollapse[collapseimg_anouncement].gif" alt="" border="0" /></a>
<b>vBulletin.org Modifications Announcement</b>
</td>
</tr>
</tbody>
<tbody id="collapseobj_announcement" style="$vbcollapse[collapseobj_announcement]">
<tr>
<td class="alt1" width="100%"><p>All modifications have now been moved to their own section of the site. To access the modifications, please click either the modifications tab or link in the navbar.</p>
<p>This announcement can be collapsed when you have read it.</p></td>
</tr>
</tbody>
</table>
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