Conversion code

[Pellot]

Hi! i'm Fabrizio and i have a problem with my site. I use Joomla 2.5 + Virtuemart 2.0 and I must insert the conversion code of AdWords in my thanks page, after a purchase. I don't know how I can do it. I know that i must edit order_done.php and paypal.php (right?) but if I insert the code in the first page, i see an error when I buy a product.  this is the code:

Code Select Expand

<!-- Google Code for vendita Conversion Page -->
<script type="text/javascript">
/* <![CDATA[ */
var google_conversion_id = 985024181;
var google_conversion_language = "en";
var google_conversion_format = "2";
var google_conversion_color = "ffffff";
var google_conversion_label = "PdWBCLOD4wQQtY3Z1QM";
var google_conversion_value = 0;
/* ]]> */
</script>
<script type="text/javascript"
src="//www.googleadservices.com/pagead/conversion.js">
</script>
<noscript>
<div style="display:inline;">
<img height="1" width="1" style="border-style:none;" alt=""
src="//www.googleadservices.com/pagead/conversion/985024181/?value=0&amp;label=PdWBCLOD4wQQtY3Z1QM&amp;guid=ON&amp;script=0"/>
</div>
</noscript>

I don't know if i can simply copy this code in the page .php or I must to modify the code. thanks for the help

[Pellot]

no one can help me?