At the moment (May 2012) No. 42 is for sale somewhere in the middle of France. Here are some pictures of it. Unfortunately we don't know much about it's history, we will welcome extra information. EDIT We had a short message from the new belgian owner and aare hoping for more...
Here's the ad's link http://www.anciennes.net/annonce/201149373-Ventes-Auto-CITROEN-M35-n-42.html?fk=1&rec=citroen