The provisions of this chapter or chapter 37-12-02 of the North Dakota Administrative Code relating to bumpers, tires, and fenders do not apply to street rod motor vehicles. However, a street rod must have all equipment, in operating condition, which was specifically required by law as a condition for its sale when it was first manufactured. A street rod is a modernized motor vehicle which was manufactured before 1949 by a recognized manufacturer and which retains the general appearance and original body configuration as manufactured or a motor vehicle designed and manufactured to resemble such a motor vehicle. A street rod may have improved modifications to the body, chassis, engine, brakes, power train, steering, and suspension systems either by modifying the original equipment or replacing original parts with fabricated parts or those taken from other existing vehicles. The director may adopt rules to implement this section.