As Byron pointed out the HZ was never released with a 6cyl so the Tyre placard had to have changed from HX. But in no way do I agree that the Statesman placard would ever have been used.
Personally I feel all HZ XU3 would have had 92001123.
Jason (StickThis) does the reproductions and quick search bought a page of his listing his knowledge on tyre placards.
http://holdenpaedia.oldholden.com/HQ...rd_Information
Contact him and see if he has any idea on the early HZ XU3.
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