It is hereby provided that the provisions of those sections of Act 929 as amended by Act 1272, 1973 Regular Session (Acts 1973, p. 2141), hereinafter in this section specified shall apply (except as hereinafter provided) to the supplemental pension system in the same manner in which the same provisions of the sections hereinafter specified apply to the general retirement and relief system established by Act 929. The sections of Act 929 (including any amendments thereof heretofore made) which shall apply to this supplemental pension system are the following sections of Act 929: Article VI, Section 16 (entitled Termination of Employment Ineligibility - Return of Contributions); Section 17 (entitled Payment of Return of Contributions); Section 18 (entitled Designation of Severance Beneficiary); Article V, Section 6 (entitled Refund of Erroneous Contributions); Article VII, Section 1 (entitled Liabilities of Employee Members to Fund); Section 2 (entitled False Representations); Section 3 (entitled Exemptions); Section 4 (entitled Members in Armed Forces); and Section 24 (entitled Repeal and Amendment Reservation); the provisions of Article IV, Section 8 (entitled Re-employment) provided, however, that anything in Section 18 (or any other section) of Act 929 to the contrary notwithstanding, contributions made by any deceased employee member to the supplemental pension system during his or her life shall not be payable to any person if anyone receives any benefit under Act 929 on account of the death of such deceased employee member. In the event of the death of any such fireman or policeman where no benefits are to be received under Act 929 as provided in the last clause of the last preceding sentence, and further where no benefits are payable to his or her widow or child or children under the supplemental pension system, then contributions made by such fireman or policeman to the supplemental pension system less one half of the disability benefits paid such fireman or policeman under Section 45-37A-51.06 together with contributions made by such fireman or policeman to the board of managers of the general retirement and relief system created by Act 929, and which shall be received by the board of managers of the supplemental pension system by virtue of being designated as severance nominee as provided in Section 45-37A-51.11, shall be paid to the severance nominee, if any, designated to receive return of contributions made by such fireman or policeman under the supplemental pension system, and if no such severance nominee is designated, then to the relatives of the fireman or policeman as provided in Section 18 of Act 929. In the event pension benefits accrue and will be payable to a widow or child or children under Section 45-37A-51.11, creating the supplemental pension system, then contributions made to the board of managers of the general retirement and relief system subject to return shall, anything contained in Act 929 or in the act creating the supplemental pension system to the contrary notwithstanding, be paid to the board of managers of the supplemental pension system. It is intended that Section 18 of Act 929 shall be adopted by reference only to the extent that it does not conflict with, nor shall it in any event be applied so as to conflict with or to be contrary to, provisions of the two last preceding sentences of this section. Anything in this section to the contrary notwithstanding, there shall be no return of contributions to anyone, subsequent to a retirement by a fireman or policeman under Section 45-37A-51.07 or a service retirement under Act 929 theretofore made to the supplemental pension fund by such fireman or policeman so retired. Any contributions, returnable to anyone hereunder shall be reduced by the amount of any unpaid indebtedness due to either or both this supplemental pension fund and a pension fund established under Act 929 by the employee member making such contributions and there shall be paid by this supplemental pension system to the pension fund established under Act 929 the amount of any unpaid indebtedness due it by such employee member and not payable from contributions made by such member to the pension fund under Act 929 because of the insufficiency of the amount of such returnable contributions. Any provision of this section notwithstanding, any fireman or policeman who retires with 30 years of credited service under the general retirement and relief system before having accrued 20 years of credited service under the supplemental pension system shall be entitled to a return of contributions, less one-half of any disability payments made.