Notwithstanding the provisions of Kan. Stat. Ann. §§ 74-4913 to the contrary, an employee who became a member of the Kansas public employees retirement system on July 1, 1969, and who was first employed by another participating employer from July 11, 1949, to October 15, 1961, shall upon retirement be entitled to receive prior service credit for said employment prior to January 1, 1962. The prior service benefit shall be computed by using a prior service annual salary of five thousand three hundred twenty-five dollars ($5,325).