Have no pics and not sure if they would go under Chevy or import since it's a GM car on an Opel chassis design.
Aluminum center section, semi-trailing arms, and drops out on a cradle frame so should be fairly easy to adapt.
Suspect that newer CTS is similar.

The quad-cam V6 engine is surprisingly attractive and can be mated to manual trans.
Probably a PAIN to adapt to other cars though due to excessive electronics issues.