While the entire index of old Missouri death certificates (1910-1955) will go public on Thursday, only the records from 1910 to 1920 have been imaged to date. This is understandable considering the number of records involved -- over two million. Plus, this is exactly what the Archives predicted last summer when they commented on the status of the project's progress. Images of the certificates after 1920 up until 1955 will follow chronologically, so in the meantime researchers can submit a request for a photocopy.
The Archives' request policy will allow up to five (5) requests at a time by mail. When you click on the link to request a copy, you will be taken to a page explaining this policy. Another link will then take you to a PDF of an order form that you can fill out online and print.
Images of the scanned certificates are also saved as PDFs, so those without that software will want to install it before Thursday. (A note to Firefox users: Do not try to open the images in a new tab. By doing so you'll only load another page of the search results. Instead, just click on the "view image" link and a new window with the PDF will pop up.)
I'm currently finding that the search tool has a little bug. It's still possible to find the names I want, but it's taking a little longer to do so. I've reported the issue and won't comment unless it persists.