You haven't "proven" anything. The map and events speak for themselves. Elm Street should have been used.
It is quite laughable that you think that you have proven otherwise.
Oh, but I did, grasshopper.
Let me bring back CE2113.
Notice that Elm, Main, and Commerce (in fact, most of the streets in the old CDB) are shown as being wider that either the North- and South-bound carriageways of I-35E, and the Stemmons carriageways are shown as no wider than their entry/exit ramps. None of that was true. That's how we know that the map is a schematic rather than a to-scale representation of downtown streets. If you can't trust it to show that 35E was wider than Elm, Main, or Commerce, then you can't rely on it to claim Elm was as wide as Main.
Here's a photo of Dallas taken in the 50s. Seems Elm St and Main St are of similar widths, but to my eye, Elm Street looking wider.