key words are that 'some' parts, mostly internals, are interchangeable between a 3.8 and 5.0; because the 3.8 is basically a 5.0 with the front two cylinders chopped off. that's why they SCd them early, they can take the punishment like its big brother can. To SC a 4.6 requires MAD modifications to the internals before risking some serious damage.