(a) If any person actively and principally engaged in the business of selling new or used motor vehicles, trailers or semi-trailers, and registered with the department in the “dealer's class,” acquires a motor vehicle, trailer or semi-trailer for the purpose of resale, and prior to such resale, uses the motor vehicle, trailer or semi-trailer for a taxable use under this act, the person may pay a tax equal to six per cent of the fair rental value of the motor vehicle, trailer or semi-trailer during such use. This section shall not apply to the use of a vehicle as a wrecker, parts truck, delivery truck or courtesy car.

(b) A commercial aircraft operator who acquires an aircraft for the purpose of resale, or lease, or is entitled to claim another valid exemption at the time of purchase, and subsequent to such purchase, periodically uses the same aircraft for a taxable use under this act, may elect to pay a tax equal to six per cent of the fair rental value of the aircraft during such use.