Notwithstanding the provisions of Kan. Stat. Ann. §§ 74-4911 and 74-4913 to the contrary, an employee of a participating employer who was first employed by said employer on October 15, 1969, and who is employed by the participating employer on the effective date of this act shall be an eligible member of the Kansas public employees retirement system as of November 1, 1969, on the payment of the appropriate employer and employee contributions, and shall be entitled to receive full credit for employment with said participating employer, from said date of membership. Upon attainment of membership by the provisions of this act, such employee shall receive prior service credit for all service as an elected official of a county for service from January 9, 1939 to January 14, 1957. The prior service benefit shall be computed by using a prior service annual salary of five thousand six hundred fourteen dollars and fifty-two cents ($5,614.52).