Hello everyone who responded - thanks for the help. This is the change I made to includes/classes/order.php:

old line: tail . $email_order;

new line: tail . $email_order = $pmt_details . $email _ order;

Now I receive:

tails . $email_order = $pmt_details . $email_order; $html_msg['EMAIL_TEXT_HEADER'] = nl2br($pmt_details) . $html_msg['EMAIL_TEXT_HEADER']; } zen_mail('', SEND_EXTRA_ORDER_EMAILS_TO, SEND_EXTRA_NEW_ORDERS_EMAILS_TO_SUBJECT . ' ' . EMAIL_TEXT_SUBJECT . EMAIL_ORDER_NUMBER_SUBJECT . $zf_insert_id, $email_order . $extra_info['TEXT'], STORE_NAME, EMAIL_FROM, $html_msg, 'checkout_extra', $this->attachArray); } $zco_notifier->notify('NOTIFY_ORDER_AFTER_SEND_ORDER_EMAIL'); } } ?>

Did I do this correctly? Any more help is appreciated!