I am sorry to ask, but i have no php knowledge. Can you point exactly how/where  this code is inserted?
I believe this is the display > view section of the billing/shipping address where I would like the email address to come after:
current output:     Mr. Customer
123 Main St.
92081 Vista, CA
United States of America
Telephone: 619.345.3422
Add email Here   xxxxxxxxxx
 <table width="100%">
          <tr>
            <?php if($this->invoice_type=='full' && !empty($this->element->billing_address)){?>
            <td>
              <fieldset class="adminform" id="htmlfieldset_billing">
              <legend style="background-color: #FFFFFF;"><?php echo JText::_('HIKASHOP_BILLING_ADDRESS'); ?></legend>
                <?php
                  $class = hikashop_get('class.address');
                  echo $class->displayAddress($this->element->fields,$this->element->billing_address,'order');
                ?>
              </fieldset>
            </td>
            <?php }?>
            <td>
            <?php
              if(!empty($this->element->order_shipping_id) && !empty($this->element->shipping_address)){
                ?>
                <fieldset class="adminform" id="htmlfieldset_shipping">
                  <legend style="background-color: #FFFFFF;"><?php echo JText::_('HIKASHOP_SHIPPING_ADDRESS'); ?></legend>
                  <?php
                    if(empty($this->element->override_shipping_address)) {
                      $class = hikashop_get('class.address');
                      echo $class->displayAddress($this->element->fields,$this->element->shipping_address,'order');
                    } else {
                      echo $this->element->override_shipping_address;
                    }
                  ?>
                </fieldset>
                <?php
              }
            ?>
            </td>
          </tr>
        </table>