Jason,
I can't actually answer this question for you. But I just installed a Repro 70-72 Cowl Ind hood (for about half the price of a GM hood), and if 66 and 70 repro hoods are made by the same company (call and ask one of the vendors if they are), then you will probably be very satisfied. After I got mine painted, I bolted it together, adjusted the fit and it is perfect. My son has an original CI hood on his 71, and so far I can't tell any noticeable difference between the 2.
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