The above standards instruction provides guidance on LED light bar use, suggesting the use of paired LED bars, or installing a "Blanking Plate" for a large centrally mounted LED light bar to be used as an additional "driving light".
As the LED light bar is only to be used as a driving light (not for low / dipped beam use), then it only needs to comply with requirements in ADR 13/00 and NOT ADR 46/00.
(ADR 13/00 - Installation of Lighting and Light-signalling Devices on other than L-Group Vehicles 
Vehicle Standard (Australian Design Rule 13/00 - Installation of Lighting and Light Signalling Devices on other than L-Group Vehicles) 2005)
(ADR 46/00 - Headlamps 
Vehicle Standard (Australian Design Rule 46/00 - Headlamps) 2006)
ADR 13/00 "Additional Lamps" states:
    6.1.5. In addition to the main beam headlamps in paragraph 6.1 of Appendix A, a further two or four driving lamps may be installed as long as they comply with clause 7.3 of this standard.
    7.3. DRIVING LAMPS
    7.3.1. Presence: Optional on motor vehicles. Prohibited on trailers.
    7.3.2. Number:
    7.3.2.1. Two or four.
    7.3.2.2. To be used in conjunction with headlamps.
    7.3.3. Arrangement: No individual specifications
    7.3.4. Position:
    7.3.4.1. In width: no individual specifications.
    7.3.4.2. In height: no individual specifications.
    7.3.4.3. In length: at the front of the vehicle and fitted in such a way that the light emitted does not cause discomfort to the driver either directly or indirectly through the rear-view mirrors and/or other reflecting surfaces of the vehicle.
    7.3.5. Geometric visibility: No individual specifications.
    7.3.6. Orientation: Towards the front.
    7.3.7. Electrical connections: The driving lamps must be able to be lighted only when the main-beam headlamps switch is in the “lamps on” position.
    7.3.8. Tell tale: No requirement.
    7.3.9. Others: The aggregate maximum intensity of the main-beam headlamps as specified in paragraph 6.1.9.1 of Appendix A, can be exceeded with the fitment and illumination of driving lamps. Driving lamps do not have to comply with ADR 46/...
ADR 13/00 also allows the use of "Alternative Standards", referring to the European UNECE Regulation No. 48, and actually has this listed as Annex A to ADR 13/00.