[With regard to any county which is required to operate on a countywide system of road administration as described in Section 19-2-3, this section shall read as follows:]
The board of supervisors of each county, at its next regular or special meeting after receipt of notice of the amount of money apportioned such county, shall spread upon the minutes of such meeting the roads and bridges selected by it to be constructed or improved. In the selection of such projects the boards of supervisors shall select roads and bridges which will be of the greatest benefit to the county as a whole, judged from the standpoint of relative use and importance. However, if the board of supervisors selects a portion of the federal aid farm-to-market system, as set up in Sections 65-11-1 through 65-11-37, then the road shall be built up to the specifications for the federal aid farm-to-market system, and the funds made available under Sections 65-11-39 through 65-11-59 shall be expended under the provisions of the former sections. No reference is intended to any order of the board of supervisors heretofore made with reference to farm-to-market roads in the respective counties.