C8AX Tac Sign

[Ausmick]

I started to lightly sand off the three layers of fire engine red from the little C8AX I have for a project trying to find some unit signs or ARN. I came to a light oliver colour and on both the left and right cowl sections this came through:
RN
68022
To my suprise, I was looking for a NZ Kiwi 3rd Division sign, so sanded some more. I found the white Kiwi Bird on the left cowl, but on the right Cowl I sanded up a tac Sign:
102
This is on a black brackground, and the truck was now a dark green. I did a search on it and came up with, to my suprise, NZEF 102VDTC being the 102 mobile VD Treatment centre!. Does anyone know if this is right and what the Aussie RN over 68022 stands for? (and hold back the jokes about my poor C8AX if the signage is right. I have already read history about the 102VDTC attached to the NZ 2nd Div Italy.)