Motor Co. will give up majority ownership of two Canadian aluminum casting plants in Windsor, Ont., to Nemak, its joint venture with ALFA of Mexico, to gain dominance in aluminum casting and pursue more non-Ford business. Ford of Canada President Bobbie Gaunt made the announcement in Windsor that the two have signed a memorandum of understanding with an agreement to be finalized by year's end. The 1,140 workers remain Ford of Canada employees under the three-year Canadian Auto Workers agreement, but they will be assigned to Nemak. Ford has had a 20% stake in Nemak since 1981; ALFA has 80%. There is no cash infusion. Ford says it will end up owning far more than 20% of Nemak after the transaction.