For regulations under section 7641, except the provisions thereof relating to the manufacture of opium suitable for smoking purposes, see subparts E, F, G, and H or part 45 of this chapter (Miscellaneous Stamp Tax Regulations). For regulations relating to the manufacture of opium suitable for smoking purposes, see 26 CFR (1939) 150 (Narcotics Regulations 3, 3 FR 1402) as made applicable to section 7641 by Treasury Decision 6091, approved August 16, 1954 (19 FR 5167).