(a) This subsection shall apply to every county in the state except a county subject to the provisions of subsection (b) of this section. During the month of August, 1943, and during the month of August of each fourth year thereafter, the county commission of each county, the county board of education and the governing body of the largest municipality in each county shall each submit in writing to the state Commissioner of Revenue the names of three persons, and the governing body of each other incorporated municipality within the county shall, in like manner, submit the name of one person, all of whom are residents of the county, who are each owners of taxable property which is located within this state, who are each qualified electors in said county and who are, in the opinion of said nominating body, persons competent to serve as members of the county board of equalization. In those counties where there is no incorporated municipality, the commission of said county shall nominate six persons as competent persons for appointment to membership on such board of equalization. From each group of three nominees, submitted by the county governing bodies and the county board of education and from the total group of nominees submitted by the governing bodies of the municipalities, the Commissioner of Revenue, within 30 days after receipt of such lists of nominees, with the approval of the Governor shall appoint one person to membership on the county board of equalization so that the membership of said board shall be composed of three members, one of whom was nominated by the governing body of the county, one by the county board of education and one by the governing body of the incorporated municipalities in the county, except, however, that in those counties having no incorporated municipality, two of the three members of said board shall be selected from the six nominees of the county governing body; provided, that the Commissioner of Revenue may reject any group of nominees, in which event the body nominating them shall submit additional names, one of whom shall be appointed by the Commissioner of Revenue with the approval of the Governor. The members of the several county boards of equalization appointed from the nominees as in this section provided shall hold office for four years beginning October 1, 1943, and every fourth year thereafter. In all counties having a population of 400,000 or more persons according to the 1940 federal census or any subsequent census, where there is now or hereafter may be a countywide civil service system, all nominees must take an examination and qualify by a civil service examination to be conducted by said civil service system, except any member of any board of equalization now duly appointed as a member of said board of equalization shall be deemed qualified for appointment. In the event the names submitted by either the county commission of the county, the county board of education and the governing body of the largest municipality in said county having a countywide civil service system have already been submitted by either of the nominating parties, the Commissioner of Revenue shall so notify said nominating authorities, and said nominating authorities shall forthwith submit the names of another person or persons qualified under said civil service examination not theretofore nominated by the other nominating authorities.

(b) This subsection shall apply to any county of this state which has a population of 600,000 or more according to the last or any subsequent federal census. On October 1, 1975, the office of chairmanship of the board is created. The chairman shall be the executive officer of the board and shall supervise the assignment of duties to members and employees. The provisions of the Merit System law, including the provisions thereof governing appointment and compensation of persons subject to said Merit System law, shall apply to the chairmanship and to the chairman.

The governing body of the county shall appoint the chairman subject to the Merit System law. Any person who is serving as chairman on October 1, 1975, and who has so served for at least 24 consecutive months immediately prior to such date shall be deemed to have been appointed under the provisions of this subsection and to have acquired permanent civil service status as chairman. Any person serving as chairman on October 1, 1975, and who has served as chairman for more than 12 months and for less than 24 months immediately preceding October 1, 1975, shall be deemed to have been appointed under the provisions of this subsection and to be serving his probationary period under the Merit System law. Any person serving as chairman on October 1, 1975, who has served for less than 12 consecutive months immediately prior to said date shall be deemed to be a temporary appointee under the Merit System law and shall be required to take and pass an appropriate examination or be replaced by another applicant who has taken and passed such examination.

After October 1, 1975, the associate members of the board shall serve the remainder of the term for which they were appointed under subsection (a) of this section to serve. Upon the expiration of such term of office, mentioned in the next foregoing sentence, the associate members of the board shall be appointed in the manner hereinafter provided for in this subsection.

The county board of education and the governing body of the largest municipality in the county shall each submit in writing to the state Commissioner of Revenue the names of three persons, and the governing body of each other municipality within the county shall, in like manner, submit the name of one person, all of whom are residents of the county, who are each owners of taxable property which is located within this state, who are qualified electors in said county and who are, in the opinion of the said nominating board, persons competent to serve as members of the board.

Within 30 days after the receipt of such list of nominees, the state Commissioner of Revenue, with the approval of the Governor, shall nominate an associate member of the board from the nominees of the county board of education and one associate member of the board from the nominees of the governing bodies of the municipalities of the county; provided, that the Commissioner of Revenue may reject any group of nominees, in which event the body nominating them shall submit additional names, one of whom shall be appointed by the Commissioner of Revenue with the approval of the Governor. The associate members of the board appointed from the nominees as provided for in this subsection shall hold office for the four-year terms provided for in subsection (a) of this section.

In all counties having a population of 400,000 or more persons according to the 1940 federal census or any subsequent federal census, where there is now or hereafter may be a countywide civil service system, all nominees for the associate members must take an examination and qualify by civil service examination to be conducted by said civil service system, except any person serving as an associate member on any board of equalization on October 1, 1975, shall be deemed qualified for appointment. In the event the names submitted by either the county board of education, and the governing body of the largest municipality in said county having a countywide civil service system have already been submitted by either of the nominating parties, the Commissioner of Revenue shall so notify said nominating authorities, and said nominating authorities shall forthwith submit the names of another person or persons qualified under said civil service examination not theretofore nominated by the other nominating authorities.