Sec. 8. This Act shall not have the effect of changing any duties imposed on or powers conferred on the trustees of school districts situated in the counties covered by this Act, unless and except as expressly provided herein, it being the intention of this law that said respective Boards of Trustees shall continue to administer their lawful duties and powers except as to the levying, assessing, and collecting of maintenance taxes, and the powers and duties as to levying, assessing, and collecting maintenance taxes shall remain unaffected except as modified as provided herein.