How many products are we talking about?
I haven't worked everything out yet but here are some thoughts.
You might be able to add an extra defines file in:
includes -> languages -> english -> extra_definitions -> tracking_info_defines.php
PHP Code:
<?php
define ('TRACKING_CODE', 'Your information goes here');
?>
Now you could use an if statement at the bottom of tpl_product_info_display.php
PHP Code:
<?php if ($product_id=? || $product_id=?) echo TRACKING_CODE; ?>
I'll play around with this and see how it works.