Any Mercedes prior to U.S. model year 1981 would have a vin number starting with the chassis number. If your vin is indeed starting wiht a 126 then it is a grey market car. The W126 chassis was introduced to Germany in 1979 as a 1980 model. InGermany there model year starts in the Summer. Also, I have a full line broucher for Mercede from 1980, and there was no U.S. model 380. There was the 280 and the 450.

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1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
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