They were standard with certain engines and boxes from late HJ.

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Quote Originally Posted by Absinth View Post
Also interesting that it has carpet, armrests (on Holden door trims)....and courtesy light switches in the door jamb.

I know you say no Byron.... but I am still of the belief that armrests, carpet and courtesy lights were standard on HJ Sandman... There are too many around that have these for them to be optional and both my HJ Sandmans (Contessa Gold 75 model and Mandarin Red 76 model) back in the 80's had them...
It is very confusing. What it appears to be correct is that carpet was standard but not part of Sandman. It came with bucket seats. Armrests were definitely not specified as part of Sandman until later, but documentation can be contradictory (as with carpet). Door switches were optional, never part of HJ Sandman unless it was a Kingswood ute then it was part of Kingswood.