I've seen photos of FJ Holdens being assembled at Fishermans Bend with the odd Vauxhall Velox in the mix of sedans, utes and vans. It must have seemed odd to the guys on the line to be installing indicators in the Vauxhalls (along with 12 volt batteries) whereas the Holden didn't feature them until the FE Special. From what I can gather, the Vauxhalls had them from at least late 1953. The switch was above the horn push on the steering wheel on the earlier models and then from a stalk on the column. The Mark 1 Zephyr had the switch in the centre of the wheel. GMH must have dragged their feet with the FJ, as indicators are not listed in as an accessory in any of the brochures I've seen.