You can reuse the harness, since its the same firing order it is pretty much all the same. There are efi intakes you can buy as well, but they are spendy. As for smog I don't see why not, but I don't know for sure since I didn't use any of that stuff. And for what you can get it out of, trucks, full size broncos, the older full size vans, and I think the LTD but im not sure. If you can I would get a 94 and newer block since it is a roller block