[Silver_2000_)!]

Im changing from Openx and adsense to double click for publishers

The challenge IM running into is how to manage multiple ads on the forum
Currently the system ( as I understand it ) requires me to add code to the headerinclude like this

<script type='text/javascript'>
var googletag = googletag || {};
googletag.cmd = googletag.cmd || [];
(function() {
var gads = document.createElement('script');
gads.async = true;
gads.type = 'text/javascript';
var useSSL = 'https:' == document.location.protocol;
gads.src = (useSSL ? 'https:' : 'http:') + 
'//www.googletagservices.com/tag/js/gpt.js';
var node = document.getElementsByTagName('script')[0];
node.parentNode.insertBefore(gads, node);
})();
</script>

<script type='text/javascript'>
googletag.cmd.push(function() {
googletag.defineSlot('/xxxx784/nt_footer', [728, 90], 'div-gpt-ad-xxxyyyy515-0').addService(googletag.pubads());
googletag.defineSlot('/xxxx784/nt_header', [728, 90], 'div-gpt-ad-xxxyyyy515-1').addService(googletag.pubads());
googletag.defineSlot('/xxxx784/nt_in_thread', [728, 90], 'div-gpt-ad-xxxyyyy515-2').addService(googletag.pubads());
googletag.defineSlot('/xxxx784/nt_photo', [180, 150], 'div-gpt-ad-xxxyyyy515-3').addService(googletag.pubads());
googletag.pubads().enableSingleRequest();
googletag.enableServices();
});
</script>

and put pieces of this in the correct places

<!-- nt_footer -->
<div id='div-gpt-ad-xxxyyyy515-0' style='width:728px; height:90px;'>
<script type='text/javascript'>
googletag.cmd.push(function() { googletag.display('div-gpt-ad-xxxyyyy515-0'); });
</script>
</div>

<!-- nt_header -->
<div id='div-gpt-ad-xxxyyyy515-1' style='width:728px; height:90px;'>
<script type='text/javascript'>
googletag.cmd.push(function() { googletag.display('div-gpt-ad-xxxyyyy515-1'); });
</script>
</div>

<!-- nt_in_thread -->
<div id='div-gpt-ad-xxxyyyy515-2' style='width:728px; height:90px;'>
<script type='text/javascript'>
googletag.cmd.push(function() { googletag.display('div-gpt-ad-xxxyyyy515-2'); });
</script>
</div>

<!-- nt_photo -->
<div id='div-gpt-ad-xxxyyyy515-3' style='width:180px; height:150px;'>
<script type='text/javascript'>
googletag.cmd.push(function() { googletag.display('div-gpt-ad-xxxyyyy515-3'); });
</script>
</div>

trouble is that ANY small change to ANY of the ads requires all the code to be updates since the ad numbers change

Im JUST starting to use DFP and maybe im missing something basic

Ideas - suggestions and face palms welcome