No permitted sign shall extend above curb level at a height greater than 20 feet or obstruct an arcade.

Within Subdistrict B, permitted signs facing upon West 65th Street shall not exceed a height of 40 feet above curb level, and permitted signs facing upon Broadway between West 65th Street and West 66th Street shall not exceed a height of 60 feet above curb level. However, signs facing in an easterly or southerly direction upon that portion of the public place designated on the City Map that is located within an area bounded by West 65th Street and the prolongation of the south side of West 64th Street shall not exceed a height of 40 feet above the level of such public place.