Anyone who wants to know where you edit the content if you prefer NOT to use the Define Page Editor.

\includes\languages\english\html_includes\YOUR_TEMPLATE\define_middlebox_1.php


If you wish to chaneg the Title of the Sideboxes you will need to edit:

\includes\languages\english\extra_definitions\YOUR TEMPLATE\


middlebox_1.php
middlebox_2.php
middlebox_3.php

Edit: define('BOX_HEADING_MIDDLEBOX1', 'Put your title here');