[kh99]

I think I can help a little - I think you'd want:

    
if (!is_member_of($vbulletin->userinfo, array(X, Y, Z)))
{
    unset(
        $userinfo['field1'],
        $userinfo['field2'],
        $userinfo['field3']
    );
}

but I don't know which hook location to recommend.

Edit: do you mean that you don't want to show the fields if it's the profile of a user in one of those groups, or do you mean you don't want to show anyone's field1, field2, etc to someone of one of those usergroups?