The board of supervisors is further authorized and empowered to paint center line safety stripes on all state aid roads heretofore or hereafter constructed in the several counties, by the use of its own crews and facilities or by public contract. The striping shall be applied of the materials and in the manner as the State Aid Engineer shall require. The board, subject to the approval of the State Aid Engineer, may include such striping in the same contract for the completion of the state aid road itself, or by a separately advertised and awarded contract. Funds necessary to carry out this section shall be as provided in the construction of the state aid road itself. The State Aid Engineer is authorized to promulgate and adopt reasonable regulations he may deem necessary and requisite in carrying out the provisions of this section.