Overtime and job anxiety for GM's Delphi workers. (General Motors Corp workers at two Oak Creek, WI-based Delphi plants worried over impact Delphi parts unit spinoff will have on jobs)

Employees at two Delphi Automotive Systems plants in Oak Creek are working overtime to make up for production lost during the General Motors Corp. strike this summer. Yet many workers there are feeling as insecure as ever.

Delphi workers laid off during the strike returned to their jobs in early August, right when GM announced its plans to spin off its Delphi autoparts subsidiary in an initial public offering. Justified or not, many workers are worried about how the plan will affect them.

"There's a definite concern," said Ken Thomas, president of United Auto Workers (UAW) Local 1866, which represents about 800 employees at Delphi's catalytic converter factory on South Howell Avenue.

While an independent Delphi will control its own destiny, it will also face stiff competition from other auto suppliers. The question is whether the new Delphi will try to exact concessions from the UAW to become more competitive. The company's contract with the union expires in September 1999.

GM executives "have complained for years about labor costs at …