If you aren't planning on selling the car as a S.S., then it shouldn't be a problem.This is the reason we get SO MANY posts about how to identify a real S.S. car.If you are planning on selling, there is a little thing called "FRAUD". The ' 68 up cars don't have a special serial # to determine if it is a S.S., you can look at the Vin on the ' 72 cars and see if it came with a B/B, but some S.S. cars in ' 72 had small blocks .Just make sure your intentions are good, and let all potential buyers know of the changes you made if you ever do decide to sell the car, and you will be alright. If it is for personal choice, and your satisfaction, go ahead, but still be truthful if anyone wants to know about it.
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1972 Malibu (1 st. car) Project waiting to happen / Team Chevelle # 427 / A.C.E.S. # 1282