Current trade conditions are great, except for one segment of Toyota Motor Corp.'s sales, that of T-100 pickups, which are subject to a 25% duty. Yale Giesel, Toyota's U.S. sales chief, says the duties are "ridiculous" but that his company will still sell 1 million vehicles in North America for the fifth consecutive year in 1994. Mr. Giesel says he is appealing to his superiors in Japan to build the T-100 in North America, but that won't happen for several years. In the meantime, he says Toyota will step up Previa sales in the U.S. in 1995--from 17,000 in 1994 to at least 25,000 this year. Mr. Giesel says the carmaker's U.S. market share, including Lexus, will slip slightly in 1994