Section 2008(d)(1) of Pub. L. 94–455, as amended by Pub. L. 99–514, § 2, Oct. 22, 1986, 100 Stat. 2095, provided that: “The amendments made by subsection (a) [enacting this section and amending sections 2031 and 2512 of this title]—

“(A) insofar as they relate to the tax imposed under chapter 11 of the Internal Revenue Code of 1986 [formerly I.R.C. 1954, section 2001 et seq. of this title], shall apply to the estates of decedents dying after December 31, 1976, and

“(B) insofar as they relate to the tax imposed under chapter 12 of such Code [section 2501 et seq. of this title], shall apply to gifts made after December 31, 1976.”