another silly ´68 SS Barracuda question :)

Well I looked through my oldest NHRA Drag Ruel booklet, witch is from 1970 one more time, and under section "ignition" I found this:
Each car in competition must have a positive action on/off switch in good working order, located within easy reach of the driver, and on the same side of the car as the fuel shut-off control and hand brake. Magneto "kill-button" type switches are not permitted. It is recommended in all competition classes that the switch be mounted on either the hand brake or steering wheel. (not required in this location on cars competing in Sections V or VI)

The last remark about cars competing in Sections V and VI, I am not sure of what it means... Super Stock and Stock?? If I remember the "competition classes" also was called the Pro Classes??

So someone with a Ruel Book earlier than 1970 may be can track this ruel back in time...