Differentials for 2800cs and 3.0CS
The cases are the same and are interchangeable. Also interchange with E3, E12, E12 up to 81.
I think all 2800CS had 3.45 ratio. Here in the US, 3.0CS had 3.64 ratio, but in Europe they used 3.45. The CSi model never imported to US had 3.25s.