A Look at the expansion of Cubs Park
Here’s a May 1923 issue of Popular Mechanics detailing the slicing and moving of the stands to create a larger ballpark. Note that the diagram in the article is incorrect, as both sides of the stands had slight angles to them after the expansion, as diagrammed below the article. The GIFs below are set to loop 3 times. If they’ve stopped looping by the time you get to them, reload your browser. 
Here’s a look at the final expansion of 1923. The field was lowered, allowing for additional box seats to be added that still sloped downward to the field so as to allow for unobstructed viewing.
Original placement of Weeghman Park in red. Not only was the field shifted, it was also lowered.
Original sections of the park indicated in red.
And one more look at it, this time from the construction blueprints of the expansion.
Animated GIF constructed from the diagrams shown here at the terrific Chicago Tribune “Wrigley at 100 Years” article.
