* Sadao Yamanishi, a Japanese auto executive...

* Sadao Yamanishi, a Japanese auto executive with extensive overseas experience, has been chosen as executive vice president at Mazda Motors of America in Irvine. He comes to Mazda from being general manager of the automotive division of Sumitomo Corp. in Tokyo, where he was responsible for automobile exports to North, Central and South America. He has held posts at Mazda in New Zealand and Puerto Rico.