The provisions of Section 33-42 (Permitted Obstructions) shall apply to all buildings or other structures in R6A, R6B, R7A, R7B, C4-2A and C8-2 Districts in the Special Bay Ridge District, except that dormers may penetrate a maximum base height in accordance with the provisions of paragraph (c)(1) of Section 23-623 (Permitted obstructions in certain districts).