Within the Queens Plaza Subdistrict, the sign regulations of Section 123-40 shall apply, except that such sign regulations may be modified to permit a non-flashing sign on the rooftop of a non-residential building, provided that such sign directs attention to a business conducted within such building, where such business occupies at least 20 percent of the floor area within such building, or a minimum of 50,000 square feet of floor area within such building, whichever is less. In addition, the following rules shall apply:

1. such sign shall be located on the rooftop of a building with frontage on Queens Plaza South, Queens Boulevard, Queens Plaza East or Queens Plaza North, and the height of the rooftop on which the sign is affixed shall be at least 70 feet but not more than 150 feet above curb level;
2. there shall be no more than one such sign on a zoning lot, and no more than one such sign per establishment on any sign structure;
3. such signs shall be affixed to an open frame structure with maximum dimensions that shall not exceed 45 feet in height, as measured from the surface of the roof to its uppermost point, and 150 feet in width, as measured along its widest dimension;  
4. all writing, pictorial representations, emblems, flags, symbols or any other figure or character comprising the design of such sign shall be separate elements, individually cut and separately affixed to the open frame structure. No perimeter or background surfaces shall be applied or affixed to the open frame structure in addition to such separate elements. No portion of such separate elements shall extend beyond the maximum dimensions allowed for an open frame structure. The area of such separate elements of a rooftop sign shall not count towards the maximum surface area of a sign permitted in Section 32-644 (Illuminated or flashing signs in C4, C5-4, C6 or C7 Districts); and
5. any illumination from a rooftop sign located within 100 feet of any building containing residences, where such residences legally existed at the time of the application for a permit for such sign, shall not project into or reflect onto any residential portion of such building.