Within 100 feet of Mermaid Avenue and within 100 feet of the portion of Stillwell Avenue beyond 100 feet of Surf Avenue, all portions of a building or other structure shall comply with the height and setback regulations of the underlying district, except as set forth by the provisions of this Section. The street wall location provisions of paragraph (a) Section 35-631 shall apply, except that the street wall of a building shall rise to a minimum height of 40 feet or the height of the building, whichever is less.