Classification System. (c) Special rules (1) Rule in case of no manufacturing training expenses in any of 3 preceding taxable years (A) Taxpayers to which paragraph applies The credit under this section shall be determined under this paragraph if the taxpayer has no manufacturing training expenses in any one of the 3 taxable years preceding the taxable year for which the credit is being determined. (B) Credit rate The credit determined under this paragraph shall be equal to 6 percent of the manufacturing training expenses for the taxable year. (2) Denial of double benefit No deduction shall be allowed under this chapter for the portion of the expenses otherwise allowable as a deduction that are taken into account in determining the credit under this section for the taxable year. (3) Aggregation For purposes of this section, all persons treated as a single employer under subsection (a) or (b) or section 52, or subsection (m) or (o) of section 414, shall be treated as one person. (d) Election To have credit not apply A taxpayer may elect to have this section not apply for any taxable year. . (b) Credit To be part of general business credit Subsection (b) of section 38 of the Internal Revenue Code of 1986 is amended by striking plus at the end of paragraph (35), by striking the period at the end of paragraph (36) and inserting , plus , and by adding at the end the following new paragraph: (37) the manufacturing job training credit determined under section 45S(a). . (c) Clerical amendment The table of sections for subpart D of part IV of subchapter A of chapter 1 of the Internal Revenue Code of 1986 is amended by adding at the end the following new item: Sec. 45S. Manufacturing job training credit. . (d) Effective date The amendments made by this section shall apply to expenses paid or incurred after the date of the enactment of this Act, in taxable years ending after such date.