Allowances payable under Sections 24006 and 24007 shall be reduced by an amount equal to the unmodified benefits paid or payable under other public systems for the same impairment or impairments that qualify the member for a disability allowance under this part. With respect to workers’ compensation payments that are subject to liens under Section 4903 of the Labor Code, “unmodified benefits,” for purposes of this section, shall only include payments for temporary disability, vocational rehabilitation monthly allowance, and permanent disability.