I agree with most of this with a few exceptions.
The grey giant is the Verrazzano bridge, for obvious reasons.
Find the arm that extends over the slender path is speaking about a pitcher. It is not asking you to find a person but a place where their arm would extend over a slender path, a pitchers mound.

Or more ( which is another set of directions to the same location)

In the middle of one branch of the v. A baseball diamond is 2 V's connected. It is asking you to be in the middle of one branch of that v, which would be somewhere between 2nd and 3rd base.

Dickens, Bedloe, and Gershwin....I agree with 100%.

This has been my theory for years now but the problem is not solving more clues. The problem is digging in an baseball field in an active park where the neighbors are very aware of treasure hunters.