Who's Online SideBox change wording

Zen-cart 1.38 Cherry Zen Template nothing extra special no problems with site. Just want to change wording.

In the Who's Online sidebox

There currently are 8 guests online.

I want to change "guests" to "Customers" and "Members" to "Purchasing Customers" (When Members are actually online)

Here is the sidebox code for who's online.

Where is the wording I want to change located??

<?php
/**
 * Side Box Template
 *
 * @package templateSystem
 * @copyright Copyright 2003-2005 Zen Cart Development Team
 * @copyright Portions Copyright 2003 osCommerce
 * @license http://www.zen-cart.com/license/2_0.txt GNU Public License V2.0
 * @version $Id: tpl_whos_online.php 2982 2006-02-07 07:56:41Z birdbrain $
 */
  $content = '';
  $content .= '<div id="' . str_replace('_', '-', $box_id . 'Content') . '" class="sideBoxContent centeredContent">';
  for ($i=0; $i<sizeof($whos_online); $i++) {
    $content .= $whos_online[$i];
  }
  $content .= '</div>';
  $content .= '';
?>

Any help would be appreciated.

I actually used the developers tool kit to find the wording I wanted to change.

Found the correct language file to work with.

/includes/languages/english/whos_online.php

Thanks hope this helps someone else out somehow