Good afternoon,
This forum is an amazing resource regarding parts interchange and the differences between various Benz motors of the early 2000s. I am really impressed with the knowledge of the posters here.
I am hoping to have my mechanic swap a low-mileage 2006 Crossfire engine (M112 naturally aspirated) into my 2003 W211 Mercedes E320 (the E320 has a high mileage engine with numerous problems). Crossfire engines are much cheaper and lower mileage than C, E, SLK, or CLK-class engines near me. Supposedly R170 SLK 3.2L engines interchange with my E320 engine, so I suspect that Crossfire engines do too. I want to use as many accessories as possible from the Crossfire engine due to how worn out my E320 motor has become.

I know I need to reuse the ECU from my E320. Can the Crossfire wiring harness be used or must I have the E320 harness swapped over?
Anything else I should warn my mechanic about regarding this engine swap?
And does anyone have recommendations on mechanics in Chicagoland (always good to have a backup plan if mine is unwilling to do the job for some reason)?
Thanks for your assistance in getting my vehicle back on the road.