-18(2) amounts of compensation for death or disability under the Federal Employees' Compensation Act, as amended (5 U.S.C., sec. 751 et seq.); (3) amounts of overtime pay or other premium compensation; (4) benefits under the Civil Service Retirement Act, as amended (5 U.S.C., sec. 2251 et seq.); (5) annual leave benefits; and (6) other benefits related to basic compensation— the basic compensation of each employee who is a citizen of the United States shall include the rate of basic compensation established for his position, and the amount of the allowance and the differential determined, in the manner respectively provided by sections 144 and 146 of this title. § 149. Canal Zone Merit System (a) Subject to this subchapter, the President or his designee may, from time to time, amend or modify the provisions of the Canal Zone Merit System of selection for appointment, reappointment, reinstatement, re-employment, and retention, with respect to positions, employees, and individuals under consideration for appointment to positions, established by regulations under authority of the President. (b) The Canal Zone Merit System, irrespective of whether the employees or individuals concerned are citizens of the United States or citizens of the Republic of Panama, shall: (1) be based solely on the merit of the employee or individual and upon his qualifications and fitness to hold the position concerned; and (2) apply uniformly within and among all departments to positions, employees, and individuals concerned. (c) The Canal Zone Merit System shall: (1) conform generally to policies, principles, and standards established by or in accordance with the Civil Service Act of January 16, 1883, as amended and supplemented; and (2) include provision for appropriate interchange of citizens of the United States employed by the Government of the United States between the merit system and the competitive civil service of the Government of the United States. § 150. Salary protection upon conversion of compensation base Whenever the rate of basic compensation of an employee heretofore or hereafter established in relation to rates of compensation for the same or similar work in the continental United States is converted under authority of section 144 of this title to a rate of basic compensation established in relation to rates in areas other than the continental United States in the manner provided by section 144(b) of this title, he shall, pending transfer to a position for which the rate of basic compensation is established in relation to rates of compensation in the continental United States in the manner provided by section 144(b) of this title, and as long as he remains in the same jiosition or in a position of equal or higher grade, continue to receive a rate of basic compensation not less than that to which he was entitled immediately prior to the conversion. § 151. Review and adjustment of classifications, grades, and pay level; by department An employee may request at any time that the department in which he is employed: (1) review the classification of his position or the grade or pay level for his position, or both: and (2) revise or adjust such classification, grade, and pay level, or any of them, as the case may be.