This popped up on the MK I forum:
http://mk1-forum.net/viewtopic.php?f=5&t=29122 (http://mk1-forum.net/viewtopic.php?f=5&t=29122)
There have been some pretty good articles in the past, this appears to fill in some gaps.
Just realized you have to be a member on the MK I forum. Here is the link to the article:
http://maximummini.blogspot.com/2020/06/breaking-news-following-mike-gartons.html (http://maximummini.blogspot.com/2020/06/breaking-news-following-mike-gartons.html)
The Le Mans story is here:
http://maximummini.blogspot.com/2011/07/minis-at-le-mans-1967.html (http://maximummini.blogspot.com/2011/07/minis-at-le-mans-1967.html)
His blog is difficult to follow with stories scattered over many posts.
here is an overview:
https://www.hemmings.com/stories/article/lost-found-49 (https://www.hemmings.com/stories/article/lost-found-49)