pulled the 99 4.6 and trans placed a 2002 5.4 and trans, used all harnesses from the 4.6. Luckally i got the 5.4 pcm in the deal, but i will use the 4.6, get it specailly tuned for the 5.4. I bought pacesetter long tube headers, tossed the manifolds too. The torque converter is different in the 5.4 vs the 4.6, unless your 97 was a 5.4. Camarothatcould used his 4.6 torque converter so i think it will be alright! 03 will go in just fine, but if i were YOOU, i would get the trans and torque converter with it, always talk em' down. If its a personal seller, tell them to keep in mind with the price that there is no warranty against something not running. For instance, mine came from a rolled truck, no warranty, i got it for a goooood price.