The Secretary shall issue any final regulations necessary to implement the provisions of this part (not including the provisions of sections 4562(d), 4563(d), and 4564(d) of this title, relating to transition housing goals) not later than the expiration of the 18-month period beginning on October 28, 1992. Such regulations shall be issued after notice and opportunity for public comment pursuant to the provisions of section 553 of title 5