Regulation 42 of the Principal Regulations is amended as follows:(a) by omitting from subregulation (1) "vehicle" first occurring and substituting "light vehicle" ;(b) by omitting from subregulation (1A) "vehicle" and substituting "light vehicle" ;(c) by omitting from subregulation (2) "motor vehicles" and substituting "light motor vehicles" ;(d) by omitting from subregulation (2) "trailers" and substituting "light trailers" ;(e) by omitting from subregulation (3) "trailer" first occurring and substituting "light trailer" ;(f) by omitting from subregulation (5) "bus" first occurring and substituting "light bus" .