I have updated this thread with observations from a 12/73 US coupe. What I found interesting is the early plastic expansion tank (much different from later plastic tanks), the fender cladding has changed slightly and strut bearing nuts.
e9coupe.com
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E9 Changes: '69 to '74
Changes from 2800CS to 3.0CS for US/NA Market Mechanical and Engine Bay Changes Engine enlarged from 2.8L to 3.0L, US compression revised from 9.0:1 to 8.0:1, early 2800CS oil pan has no baffles and oil pressure switch is mounted at lower end of head vs. upper portion of head Water pump pulley...
e9coupe.com
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