Some 350 workers at Tower Automotive were preparing in June to go on strike at a plant in Traverse City in northern Michigan after efforts to negotiate a new contract with United Auto Workers union representatives broke down. After numerous attempts to organize the stamping supplier, workers finally voted for UAW representation last summer. But plant sources say the company and union have been unable to reach agreement on a contract. Employees at a Tower plant in Clinton Township, MI, also were preparing to strike, but sources say management and the union reached a tentative agreement in June.