I looked up the part number for both model years. They are the same, so it should be straightforward. I attached the part numbers below
2000 Mustang 3.8L 2R3Z3504CARM
2004 Mustang 3.8L 2R3Z3504CARM
I attached the directions for removal and replacement for the rack below. Let me know if that helps or if you have other questions.
See pics below.
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Thursday, August 26th, 2021 AT 8:21 PM