If I recall correctly when I was thinking about doing the same in my 95 (selling for $1k btw), it's just the k member that needs to be changed. Pull one off one at the junkyard and it should bolt up. Don't know what year your talking though
HIS: "Night-Mare": 2012 Mustang GT/CS, Black on Black, MT, 3.73 Gears, HID's, Security/Comfort/Electronics Packages. #2 of ????
HERS: "Blue Steel": 2012 Mustang V6, Kona Blue, AT.