Whenever a district has been formed under this part and a bonded indebtedness has been incurred for public parking facilities as provided in this part, proceedings may later be taken hereunder for the further acquisition or improvement of public parking facilities for the district and the issuance of bonds therefor as provided in this part. Any such proceedings may be initiated by the filing with the clerk of the legislative body of either a petition by the owners of real property in the district or a certified copy of a resolution adopted by the parking place commission. Any such petition or resolution shall request such proceedings and, with respect to the proposed proceedings, additional acquisitions, improvements and bonds therein requested, may contain any matters authorized and shall contain any matters required in an original petition, except that it shall not be necessary to describe the boundaries of the district. The petition shall be signed, filed and certified in the same manner provided in this part for an original petition. Thereafter the procedure specified in this part for the formation of the district and the issuance of the initial bonds shall be followed so far as applicable; provided, however, that at the hearing the legislative body shall have no power to change the boundaries of the district and the acquisitions and improvements finally ordered to be made must be ones which the legislative body, following the hearing, finds to be of benefit to the district as originally formed.