(1) The department has full power, and it is made its duty, acting through its commissioner, to cooperate with the federal government in formulating and adopting a uniform system of numbering or designating roads of interstate character within this state, and in the selection and erection of uniform danger signals and safety devices for the protection and direction of traffic on those highways.
(2) The department is empowered to expend out of the funds of the department any and all amounts necessary in the carrying out of this section.
(3) The department has full power, and it is made its duty, acting through its commissioner, to formulate and adopt a manual for the design and location of signs, signals, markings, and for posting of traffic regulations on or along all streets and highways in Tennessee, and no signs, signals, markings or postings of traffic regulations shall be located on any street or highway in the state regardless of type or class of the governmental agency having jurisdiction of the streets and highways, except in conformity with the provisions contained in the manual.