Your car is a 220 six cylinder 2.2 liter. No need to research VIN numbers. Your chassis number starts with a 187, right?, and all 187's are 220's. End of story, unless you need to prove to the authorities what it is.
As for the printed material you have, don't believe everything you read in print. There are many mistakes in magazines and books, even impressive "coffee table" books" with lots of great pictures. Sometimes there are mistakes even in MB literature. As I recollect, there is a dimension mm to inches conversion mistake in the 170 manual regarding some critical engine spec. like piston clearance. And there are others I have found, but don't remember at the moment.