In the March/April 1996 issue of The Early Bird magazine, Dick Flynn submitted an article on how to replace the rear main seal with the engine in the car. Attached is the article I scanned for you. When this article was written the neoprene rear main seal was not available for the Thunderbird engine, that’s why the author is using a rope type seal. I hope this is the information that you are looking for.
doug7740
1955 Thunderbird Blue