In the case of prefabricated houses, the following special provisions shall apply:
   (a)   Such buildings or structures shall be moved only by motor truck.
   (b)   Each such truck shall be manned by a driver and two assistants equipped with red flags mounted on sticks. One assistant shall be stationed in front of the truck and one behind to warn traffic.
   (c)   Such trucks shall yield the right of way to all other vehicles whenever necessary and possible.
      (1979 Code 116.43)