That's the standard pre-facelift bumpers/skirts, but I agree they've been repainted as normally the lower section (bumpers, skirts, Sacco panels) is satin finish on earlier cars, and contrasting depending on main body colour.
You're not wrong, the sensors have just been drilled into the lower lip of the stock bumper. Pre-facelift foglights have a projector style inner lens within the main housing.
I have W210 E55 wheels on my R129. They are staggered wheels with rears being either 18x9 or 18x9.5 , I can't remember. The tire size is 275/35R18 which is bigger than the stock rear tire size on my S55K. They fit the arches well.
Those are probably from a C43 which is a square setup 18x8(or 8.5).