I'm planning on swapping my current 2002 4.6l with a 5.4l 4v from a navigator, along with replacing my stock auto trans with a 6-speed T56 magnum. Was considering just using the stock cylinder heads and cams with a swapped intake manifold and throttle body, but I'm also intrigued by the idea of using heads from the 4.6l cobras, would this give any actual performance differences or just an expensive piece of vanity? Also wondering what intake manifold would be most recommended. I'm thinking either the boss 290/302 or the Sullivan, was also considering using a used 4.6l cobra one as well. Moreso trying to build a fun car, not really a performance car, so something cost effective and enjoyable is all I need. I'll probably post more about the actual swap and