Graham and all,
This is fascinating! Thanks for sharing.
You may already be aware – Jerome Collignon’s site https://jeromecollignon.blog4ever.com/identifier-un-roadster-traction is all about early Tractions and he has a section on early roadsters. It’s really about the French cars and it may or may not have some answers. It’s a great place to get lost for a few hours anyway.
Chris
Chris