Chrysler built a majority of the Wright R-3350 engines used for the Boeing B-29 Superfortress in it's Chicago Dodge plant..You are course course spot on, I was having a brain fart maths wise. 5 banks not 6, 30 cylinders, not 36. Plus 5 distributors and 5 carburettors.
On the face of it an abortion, but Brit tank crews apparently quite liked them they were easy to look after, ran well and did not require the pre-start hand cranking that the radials needed. You could probably not tip petrol down a drain faster though.
You would have thought that they would have ditched it as a concept as soon as something else came along (like the GAA) but ooooo no.
There is a website out there somewhere that lists the production output of the larger US industrial concerns in WW2. I was astonished to see that they made over 44000, yes 44 thousand, multi banks.