Mine is an 804 build; the facelift came in for the 2015 MY.
I need a replacement because I have a shedload of fault codes, nearly all related to the Central Gateway. The iCarsoft scans both the Central Gateway and the Front SAM, but I don't think that means they have to be physically separate.
The first part number I gave - A2129008228 - is for a 2017 CLS63, and is specifically stated to be the Central Gateway. The 2017 is definitely a facelift, which would also fit with it being the pre-facelift that has the integrated unit.
Item 10 in the diagram I definitely have; I've seen it, and the part number is correct. That suggests I don't have item 120, which is shaded pink, and not on the list, whereas item 10 is on the list, and not in pink.
Once I can confirm I have the integrated unit, where do I find the front SAM? Is it under the black plastic cover at the rear of the engine bay on the driver's side?