That portion of United States highway 169 from the northern boundary of Allen county then south to the southern boundary of Allen county is hereby designated the Robert V. Talkington highway. The secretary of transportation shall place signs along the highway right-of-way at proper intervals to indicate that the highway is the Robert V. Talkington highway, except that such signs shall not be placed until the secretary has received sufficient moneys from gifts and donations to reimburse the secretary for the cost of placing such signs. The secretary of transportation may accept and administer gifts and donations to aid in obtaining and installing suitable signs.