Chairman and acting CEO Ed Whitacre figures the search for a new General Motors Co. chief executive could take as long as a year, says Bloomberg News.

The news service quoted from a recording of Whitacre’s internal broadcast to GM employees yesterday after the sudden resignation of CEO Fritz Henderson. Whitacre says the company has hired an executive search firm, but he did not identify it.

Whitacre says the next CEO doesn’t necessarily have to come from outside the company. But Vice Chairman Bob Lutz tells the Detroit Free Press that Henderson’s replacement will “very definitely” be an outsider. If the board had wanted to promote from within, it would have done so immediately, he says.

Analysts predict GM will look for an executive with manufacturing and corporate turnaround experience. Federal pay caps, which cut Henderson’s salary to $950,000, could make it tough to attract top talent, although analysts expect the government to ease restrictions in GM’s case. Whitacre says the company might be able to offset a relatively low salary with a rich package of stock options tied to performance.

Analysts say it could be hard to find someone willing to step into a demanding job at a company controlled by the U.S. government. They suggest a high-powered hire would demand greater independence than the board allowed Henderson. With all the difficulties, some analysts speculate that Whitacre might take the job permanently.

General Motors Co. says Marco Molinari has stepped down as CFO of its Opel unit to pursue other interests.

The company also says GM Vice Chairman Bob Lutz has resigned from Opel’s supervisory board. Last month Carl-Peter Forster quit his jobs as CEO and chairman of the Opel board.

GM has tapped Nick Reilly, president of its international operations and acting Opel CEO, and Walter Borst, GM treasurer, to fill those two supervisory board vacancies. The board will select a new chairman at its next meeting.

Opel has not yet named a new CFO. The company has said it is seeking an outsider to fill the CEO slot.

General Motors Co. has narrowed its choice of prospective bidders for its Saab Automobile unit to three, says Bloomberg News.

The news service cites unidentified sources who say GM is considering proposals from Beijing Automotive Industry Holding Co., U.S. private equity firm Renco Group Inc. and Dutch sports car maker Spyker Cars NV.

GM is reportedly considering selling some Saab assets to BAIC and liquidating the rest of the company. Bloomberg says Renco is considered less likely to prevail. Analysts question whether money-losing Spyker, which built 43 cars last year, can afford to buy Saab.

Wyoming-based investor Merbanco Inc., which expressed interest last week, says GM has ruled out its bid.

Daimler AG says it will begin building its Mercedes-Benz C-Class at its assembly plant in Tuscaloosa, Ala., when the revamped model debuts in 2014. The factory will account for one-fifth of the production of the company’s top-selling vehicle line.

Daimler says shifting the work from a plant in Sindelfingen, Germany, will lower costs by €2,000 ($3,020) per vehicle. The move is intended to lower labor and shipping costs and insulate Daimler from currency swings.

Workers in Sindelfingen protested the expected move earlier this week. The factory there, which produced nearly 400,000 vehicles last year, is the company’s largest assembly plant worldwide. Daimler says it will transfer assembly of the lower-volume SL roadster to Sindelfingen in 2014 and will offer other jobs to some of the plant’s employees.

Daimler says it will continue to produce the C-Class in Bremen, Germany, and in China and South Africa. The Tuscaloosa plant, which makes the GL- and M-Class SUVs and R-Class crossover vehicles, produced 152,600 vehicles last year. The company plans to add 1,000-1,200 jobs at the U.S. plant when C-Class production gets underway.

France’s PSA Peugeot Citroen says it is discussing a “strategic partnership” with Japan’s Mitsubishi Motor Corp.

PSA says the companies could extend existing agreements, which include developing electric vehicles and running a joint venture in Russia. The French company plans to begin selling a version of MMC’s i-MiEV electric city car in Europe by late next year.

The Nikkei newspaper, which doesn’t cite its sources, says PSA might buy a 30%-50% stake in MMC. The Japanese company says an equity tie-up is one of the options being discussed.

The usually loquacious Bob Lutz, vice chairman of General Motors Co., vowed yesterday to keep mum about the story behind CEO Fritz Henderson’s abrupt resignation.

Lutz, who was delivering a speech at the Los Angeles auto show in Henderson’s stead, said GM management was “totally surprised” and saddened by the news. He called the timing of the CEO’s exit “particularly inopportune.”

Lutz told reporters he knew they wanted the “true inside story” of what happened. But he pledged to “exercise enormous skill in the non-answering of your questions.” Lutz, the author of several books, joked that they would have to wait until he published the next one to find out.

Separately, Lutz tells the Detroit Free Press he isn’t likely to be asked to take the CEO job because of his age (77) and brash leadership style. He says boards prefer someone calm and uncontroversial who can be relied on to never embarrass the company-a description he readily admits doesn’t fit him.

Campbell-Ewald Advertising has named Bill Ludwig, its chief creative and strategic officer, to become its chairman and CEO on Jan. 1.

Ludwig, who joined the agency in 1984, will succeed Tony Hopp, who is retiring after 13 years in those jobs.

General Motors Co.’s Chevrolet brand is the Warren, Mich.-based agency’s biggest client. GM, which has been breaking ties with some longtime agencies in recent months, said in October it will consider other agencies for some Chevy assignments.