Section 5
SEC. 5. Upon the first classification of municipalities provided in this Act, the provisions of existing laws, orders, rules and/or regulations referring to the first class-A municipalities shall apply to the first class or the second class municipalities, as the case may be, and those referring to the first class-B, first class, second class, third class, and the fourth and fifth class municipalities shall apply to the third class, fourth class, fifth class, sixth class, and the seventh class municipalities, respectively, as defined in this Act: Provided, That the term “first class municipalities," or "municipalities of the first class " or "municipalities belonging to the first class group," or other similar term, whenever used in any provision of existing law, order, rule or regulation not expressly amended or modified by this Act, shall, upon the initial classification of municipalities herein provided, apply to the fourth, third, second and first class municipalities as defined in section one hereof: Provided, further, That municipalities with an average total annual revenue of less than five thousand pesos shall not be subject to the financial contribution provided in section two of Republic Act Numbered Nineteen hundred and thirty-nine.