24The following classes of drivers, if issued a Class 5 driver’s licence, shall not require a licence of a different class to operate types of vehicles which ordinarily may only be operated by the holder of a different class:
(a)
any peace officer operating a motor vehicle in the performance of his duty;
(b)
any examiner appointed under the Act;
(c)
any salesman of motor vehicles operating a motor vehicle for purposes of demonstration; and
(d)
a garage mechanic or other person operating a service truck or testing a motor vehicle on the highway or calling for or delivering a motor vehicle before or after repairing or servicing it.