yes - the SLK's (V8 R171 version) are not for anyone over 6' tall.
The SLK32's in the R170 guise are even worst - especially with the AMG seats which are an inch thicker than your non AMG. I'm 5'10" and the SLK32 is "almost" too small for me.

SLK55 is a very "small" car for 600hp and a kerb weight down to 1,550kg (3,400lb) - +100kg on my slk32