Big Block was the requirement. I personslly ordered in Mar '72, and took delivery in Apr, of a Concours wagon, loaded with all pwr and air, 402, wide Muncie with a bench, the roof luggage rack, your basic loaded family wagon,--------------------------------and-----------------a Cowl Induction hood WITHOUT stripes. The salesman said I had to give him a $500. non-refundable deposit. I did. In '75 I got divorced, my ex got the wagon, wrecked it twice, let it sit and go to rust and ruin and then told our youngest son he could have what was left (EVERY PIECE WAS STILL THERE). In '97, while my youngest son was in the Navy, we located a straight '71 Malibu and cloned an SS using ALL the good stuff from the wagon (the hood was undamaged). So, to answer your question, all that was required for a CI hood was a BB.
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