Model-year identification quirks

W123s built late in a calendar year are often titled as the following model year, and mixed-cluster cars are common, so commenters use specific tells: 85-mph versus higher speedometers, tach versus clock, silver dashboard buttons (phased out in 1983), seat pleat counts, and passenger-mirror type. The definitive arbiter is the Federal emissions sticker on the radiator support behind the left headlight.