I checked out google to see if I could find some articles on your question. Here are some links that came up with technical articles.
All About Ford Brake Systems - Mustang Monthly Magazine
1966 Mustang, Problems with Brake Conversion - Ford Mustang Forums
I also wrote to one of the mustang veterans on our site that owns 3 stangs including a 66 convertible with us link to your question. Hopefully, he writes us back soon.
Auggie