My neighbor has a 74 (white, black top with a 440 he stuffed in it). He is facing the same issues, not much aftermarket support. He has to either build, modify or restore old parts to get what he wants. My point is that he IS doing it. It just takes longer. But it can be done. It's your car, cut into it if that is what you want. make it the way you want it. Otherwise you will not enjoy it.