For zoning districts in certain Special Mixed Use Districts specified by this Section, the height and setback regulations of Sections 123-63 or 123-64 shall be modified as follows:

1. In R7-2 Districts within Special Mixed Use District 15 the street wall location provisions of Section 123-651 shall be modified so that at least 70 percent of the aggregate width of street walls shall be located on the street line and shall extend to the minimum base height of 60 feet or the height of the building, whichever is less. The remaining 30 percent of the aggregate width of street walls shall be located within eight feet of the street line.
2. In R6A Districts within Special Mixed Use District 23, where such R6A District is paired with an M1-5 District, the underlying height and setback regulations applicable to an R7A District shall apply.
3. On waterfront blocks, as defined in Section 62-11, the height and setback regulations of Section 62-34 (Height and Setback Regulations on Waterfront Blocks) shall apply.