From the NCOP's which are gradually being adopted by all states it appears...
The majority of internal roll-bars or roll-cages were originally designed for use in competition
vehicles where the driver and any passengers are required to wear helmets. In normal
road use, occupants of motor vehicles do not wear helmets, therefore any modifications to the
inside of the cabin must be carefully designed to reduce the risk of injuries to all occupants in the
event of a crash.
Six-point roll-cages that have supports running down the A pillars and B pillars, and braces
running to the rear are not acceptable for normal road use as the additional forward supports are
likely to constitute an increased injury risk to front seat occupants in a crash. They typically
decrease visibility for the driver and usually prevent the correct positioning of sun-visors.
Registration Authorities may allow the use of specialised or six-point roll-cages for
competition purposes. However, in these cases, the vehicles to which they are fitted have
restricted access to the road system or are conditionally registered. Persons who wish to fit
specialised or six-point roll-cages for competition or other purposes must consult with their
respective Registration Authority for further information. These types of roll-cages are not covered
by Code LK8"
From page 41 on.
This is why I built the front ROP as the windscreen support, so its not a 6 point roll cage in the first place. A while ago talking to CAM's about the potential legality of my car, they told me that front ROP to the CAMS std was not possible so they were treated as if they were open top cars.