As discussed in the articles on custom templates, to make a custom suggest article template you'd link to suggest.php?action=addlink&catid={CATID}&custom=yes&TID=yourtemplatename . If doing this for a specific category on the 'display articles in category' page you'd use a conditional like <IF {CATID} is 5>category 5's special link: <a href="http://scripts.webmastersite.net/wsnkb/manual/suggest.php?action=addlink&catid={CATID}&custom=yes&TID=yourtemplatename">suggest link</a></IF>... you could add a custom category field to set a value with which you determine what template to link to.

When you link to a 'suggest article' page with a custom template affixed to it in the url, you will notice that it reverts to the regular template when reloading due to a file being attached or a required field being missing from the submission. You can fix this by inserting your custom template url parameters as hidden input fields in the form being submitted:

<input type="hidden" name="custom" value="yes">
<input type="hidden" name="TID" value="templatename">

The same method can also be used for the 'edit article' page.