some possibilities:
the chassis chev 125 = 125" or long box? you can measure that
max GVW 2tons would be a 1/2T, and maybe the 12CWT is Holden saying it'll carry 12 CWT, which may mean a 3/4T
I don't have a list of the AD series CDN VIN codes, but someone else here may
body trim and paint will be hard to find the codes for
top acc 12??

the 1/2T would have a single pack of 8 leaves on each side - heavy 3/4T would have 2 packs each side, 8+5 leaves - maybe the rear has been changed, or Holden did something different?

can't help more, but there's some Aussie truckers on the board who might know more about it

Bill


Moved over to the Passing Lane

"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir
"When we tug a single thing on an old truck, we find it falls off" ~ me
Some TF series details & TF heater pics