not sure what the other color name is. But shows which particular classic model was a prototype for s550 body style. Look how profiles are exactly the same.
To me personally I think the lines follow the 69-70 fastback closer than the 67-68 ones. With the little built-in rear spoiler, and the rear fenders that extend outward like hips. I thought I read/heard that the 69-70 fastback was one of the biggest inspirations to the current S550 style. I like how it has the little rear windows like the 69-70 fastbacks had. One of the reasons I bought my 17 was it so reminded me of my 70 fastback that I used to have.