Hey birdman, The 460 will fit into the car as well as the 428. So the swap with either engine will be about the same amount of trouble. But on the performance end of it I personaly think you would enjoy the 428 better. Factory they have a better respone time and also build more BHP than te 460. And the 428 is easier to obtain hot parts for. You can do a few changes maybe a carb, Headers and hotter ignition and get a good deal of performance from it. Not so easy with the 460. Hope this helps you with you dilima.
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