Answer
(this answer primarily applies to the usa, model years might differ slightly in other countries).until 1998, there were s-class coupes called the s500 and s600. they were based on the sedan design, but shorter overall, and featuring a pillarless hardtop roof (no b-pillar). in 1998, mercedes-benz changed the name. the coupes were now called cl500 and cl600. the design was not changed at this time, the names. the cl-class, as the coupes were now known, was redesigned in 2000, and again for 2007.a photograph of the 1999 cl-class can be found at this link (it is a cl500, but the cl600 is almost identical from the outside. the only difference is probably in wheel design, interior features, and of course, the changes under the hood):http://www.edmunds.com/used/1999/mercedesbenz/clclass/12573/photos.html#