A measuring device is what an instrument is, and these cars are filled with all kinds of devices for read-out information. Lights , dials, sounds of all kinds, and a liquid computer to keep it all straight. I owned a number of them back in the days when they were referred to as “foreign” cars. They weren’t easily repaired as few mechanics knew what they were then, and you can’t get them fixed now as they lack plug-in diagnostic helper aids. And to make matters even more difficult, you have to actually remove the part using conventional mechanical skills, it doesn’t just plastic snap-off. Imagine that, identify the problem without a digital tel-tale, no way! The 280 and 300SL’s were as good as it gets. Your girlfriend could drive one of these convertibles at 60 miles an hour with no head scarf, not a hair would move, the wind dynamics were so well designed. Today you can’t put your drivers window down without being wind trashed at 20mph. I don’t know whether they just came that way, but they all seemed to have beautiful women in them.