The governing body of Marengo County shall immediately upon July 30, 1979, begin deducting from the salary of the sheriff an amount equal to six percent of the annual salary paid to the sheriff. Such sum shall be deducted monthly and distributed at the end of the fiscal year to the tax collector or other person charged with the duties of collecting ad valorem taxes in Marengo County. The tax collector shall distribute this money on a pro rata millage basis to the state, county, and all subdivisions and agencies thereof except municipalities to which ad valorem taxes are paid. If any sheriff coming under this subpart shall end his or her tenure of office prior to becoming supernumerary as provided in Section 45-46-233.20, the tax collector or person charged with collecting the ad valorem taxes shall withhold from the next money collected on a pro rata millage basis a sum equal to one-half of the amount paid by the sheriff to the governing body of the county during his or her tenure in office and such sum shall be paid to the person from whom the money was collected. In the event such person dies prior to payment, the monies shall be paid to his or her spouse or beneficiary.