Malaise-era GM thought it was a good idea to use the Opel name from Germany, to sell cars made in Japan by Isuzu, at Buick dealers in the USA. https://www.youtube.com/watch?v=npGqHqiTBXs
Buick Opel Car Commercial (1978)

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The true German-made Opels sold by Buick prior to 1976 had much better styling, and much better music... is that a Hammond B3 organ? https://www.youtube.com/watch?v=oOtH8dtqzNo
1973 Buick presenting two models Opel

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