How to specify a custom field in $DefaultSearchResultFormat

Some questions about displaying custom fields in search results:

  1. Is this possible to do for queue-specific custom fields without code
    modifications?
  2. What’s the syntax for use in $DefaultSearchResultFormat in
    RT_SiteConfig.pm?
  3. What about if the field name has a space in it?

My impression is that the wiki entries alluding to this functionality
are a bit obsolete and/or need some clarification.

Thanks,
Kevin Murphy