The bonds authorized by this Act shall be sold and the proceeds used solely for the specified purpose. At the time or before issuing any such bonds, the governing body shall adopt a resolution fixing the details of such bonds and providing for the payment of the principal and interest on such bonds as the same become due out of the motor fuel tax funds allotted to such governmental unit, subject to the approval of the Department of Transportation as provided in the Illinois Highway Code.
     The proceeds received from the sale of the bonds shall be placed in a special fund in the governmental unit treasury to be designated as the “Bond Highway Fund” and thereafter in the annual appropriation bill appropriate from such fund such sum or sums as may be necessary to carry out the provisions of this Act.