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 February 1, 1974, who was first employed by the same participating employer from January 1, 1941, until April 7, 1942, who entered military service on April 7, 1942, and was discharged on November 10, 1945, who returned to employment with the same employer January 1, 1946, until January 1, 1955, who was again employed by the same employer January 1, 1957, until January 1, 1959, and who was again employed by the same participating employer January 1, 1961, until January 1, 1967, shall upon retirement be entitled to receive prior service credit for said employment prior to January 1, 1969. The prior service benefit shall be computed by using a prior service annual salary of four thousand one hundred dollars ($4,100).