Notwithstanding the provisions of Kan. Stat. Ann. §§ 74-4913 to the contrary, an employee of a participating employer who became a member of the Kansas public employees retirement system on February 1, 1969, who was first employed by another participating employer from April 26, 1944, through June 3, 1950, shall upon retirement be granted prior service credit for said employment. The prior service benefit shall be computed by using a prior service annual salary of two thousand three hundred forty dollars ($2,340).