or my favorite way… clien-side scripts =)
function stat_box(){
if (get_post_type()=='YourPostTypeSlug'){
$out = '<script type="text/javascript">';
$out .= 'var myMessage = jQuery(\'.field_type-message:contains("[stat_message_anchor]")\');if (myMessage) myMessage.html(myMessage.html().replace("[stat_message_anchor]","Lorem ipsum goes here..."))'; //changing content
$out .= '</script>';
echo $out;
}
}
add_action('in_admin_footer', 'stat_box');
and just put the text “[stat_message_anchor]” in your message