I think i have found a solution. I had a look at pictures of early Brock/HDT Commodores and noted something familiar about the 'special' air cleaner assembly. I then put a couple of pictures side by side and found out the cold air system looks like its off a 1970's Chev C10 truck! SO i bought one off eBay. All i need now is some sexy ducting and all should be good.

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