Licensees shall mark their well rigs and pump installer vehicles used by them or their employees in the well drilling or pump installer business with legible and plainly visible identification numbers.(1) The identification number to be used on rigs and vehicles shall be the licensee's license number.(2) License numbers shall be printed, upon each side of every well rig or pump installer vehicle, not less than two (2) inches high and in a color sufficiently different from the color of the vehicle or equipment so that the license number shall be plainly visible.(3) A licensee shall have thirty (30) days from the date a license is issued to properly mark all well rigs or pump installer vehicles used by him or his employees as provided in paragraphs (1) and (2).