Replace content for usergroups. In this example guests see a login info. The field itself is hidden by build in admincp permissions.
{{if \IPS\Member::loggedIn()->member_id === NULL}}
Please <a href="/login/">LOGIN</a> or <a href="/register/">SIGN UP</a> to see all related Articles, Photos and Videos of this Celebrity!
{{endif}}
{$record->customFieldDisplayByKey('related-links', 'display')|raw}