If § 303 (a) (5) of Title III of the Social Security Act (42 U.S.C. § 503 (a) (5)) and § 3304 (a) (4) of the Internal Revenue Code (26 U.S.C.) are amended to permit a state agency to use, in partial or complete substitution for grants under such Title III, for financing administrative expenditures incurred in carrying out its employment security functions, some part of the moneys collected or to be collected under the state unemployment compensation law, this title shall, by Commission proclamation and rules to be issued with the Governor’s approval, be modified in the manner and to the extent and within the limits necessary to permit such use by the Commission under this title. Such modifications shall become effective on the same date as such use becomes permissible under such federal amendments.