Ah! The Bedford CF ...
https://en.wikipedia.org/wiki/Holden_straight-six_motor
Apparently the CF was available with 2 versions of the straight six in Australasia. Something I was not aware of before but hardly surprising given it was an Oz build.
More surprising (perhaps not to bauble) is that there was an electric version of the CF manufactured between 1982 and 1987
https://en.wikipedia.org/wiki/Bedford_CF
Scroll down some way for a paragraph about it if interested.