I am using Chicago 18th (author-date, classical) for conference papers -- I have a lot of old, scanned ones. When I don't add the page numbers, the citation includes the conference "event place" and "event date" details. Once I add that, it disappears. I would like to include this information, even for "published" papers (before entering the pages it cites it at presented at...).

I understand this may not be the standard for Chicago, so will make a custom version for myself, but just need some guidance to where in the code to do that...