I really don't understand why no one has documented this by now. I'm too far away from Detroit to do it myself but surely there are some records somewhere or someone who worked on bringing the big block A's to market that would remember.
The AMA specs would tell the tale, and I know where to get 'em - the AACA library in Hershey. It's actually a project of mine to get copies of those for a few cars, so it's been on my mind to stop by the next time I head to Carlisle.
Certainly you don't need Detroit to find the answer.
