Okay, I'm super excited to report that I have exact locations for each of their stops on the trip south from Nuremberg to Marseilles and that tells us where all the rest stops were on the way. I have some of their maps and after carefully reviewing a map of France I discovered that it was actually marked!!!! I edited to add a image of the map cover just in case someone was looking for the exact same map (and I did see one on posted eBay).

Hopefully this will also help others who might be researching this topic!

Woo-hoo!!!! I am excited for you too. What a great feeling of satisfaction to find the exact points of their travels. I just love this!!!!