age of the MT CMS is about to be displayed. Before going ahead and building the page, it runs some callbacks. So your plugin simply needs to install appropriately named callbacks for a particular CMS page (or all pages), and you'll have the
alt='Coastal-Vacations' href="http://work-at-home-business-website.com/Coastal-Vacations.php">Opportunity to tinker with the contents of the page before it's displayed to the user.