Jason, I’m guessing the short block is IndyCar type to meet the stock-block rules.
Scale the stroke, should be approximately 2.2”. In the early 70s they were experimenting with the flat plane crank and the engines displaced about 207ci.
Below is a link to an old ad for one Smokey Yunick built.
https://grassrootsmotorsports.com/fo...e/37588/page1/