I was searching the Google News Archive and found that it includes the Chicago Tribune! I don't have access to the ProQuest database which provides the full text of the Chicago Tribune, and when I tried searching the Chicago Tribune's own archives on their Web site, I found that the indexing is inadequate and you often cannot find what you are looking for even if you know it is there and have the date of publication, and the descriptions of the articles often do not give you enough information to know if they will be helpful.  But if you search the Google News Archive, you can actually see a snippet of what is there and there will be a link to the article on the Chicago Tribune's Web site. You still have to pay for the article, but at least you will have a better idea of what is in it and will be able to find it by doing a search.