I am so sorry.
Yes, you have it right. That conditional gives me a malformed error though, but I think that's the right idea.
--------------- Added [DATE]1223492073[/DATE] at [TIME]1223492073[/TIME] ---------------
I think I finally got it! Your conditional was just missin' one closing parenthesis (or my browser is bad at copy/paste)
Code:
<if condition="(in_array($bbuserinfo['usergroupid'], array(5, 6)) AND $vbulletin->userinfo[field18] <> 'No') OR !in_array($bbuserinfo['usergroupid'], array(5, 6))">
Lynne you are AWESOME, thanks again so much!