Old post resurrection .......
an old saying in the resto business when it comes to original looking parts.... How do you tell the difference between a 40 year old part and a 30 year old part?
having said that... HZ and Commodore were built alongside each other in 78 and 79... The engines were the same in both... Those air cleaners look original because they probably are original... To a VB Commodore! Someone has simply put a VB Commodore air cleaner in a HZ, or possibly put a VB engine in a HZ as a replacement.
back in the day GEM replacement engines were a big business... Rebuilt engines from other cars available for immediate exchange for your worn out engine. My HJ Sandman has a GEM exchange 308 in it from a HQ that looks totally original to the car....
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