First welcome to the site. Hope you find the support and information your looking for to help with your concours related projects.
For this question you would be best served using the search feature. Not perfect but it can often provide a quicker and more complete (sometimes) answer to your questions. For this one there is likely a dozen similar or same threads. Everything from
- the best source of product for refinishing you engine correct
- list of what was installed when the engine was painted (was a lot of them) and what was not. HINT: its FAQ #11 in each section in the individual year section of the site
- Ford ad they published explaining the change
- dozens of unrestored examples with original paint still on the engines and more. You wil lfind these in the Unrestored Picture section of the site
Since our practice is to merge threads on the same subject this one will be merged with one of those longer and earlier threads
Again welcome to the site
A couple of threads but plenty more of what products worked and didn't work for members
Engine Rattle Can - Ford Corporate Blue or Old Ford Blue
https://www.concoursmustang.com/forum/index.php?topic=23318.msg145799#msg145799289 Paint process -
https://www.concoursmustang.com/forum/index.php?topic=29359.msg178706#msg178706