NORTH TARRYTOWN, N.Y. (AP) _ Workers at a GM minivan plant in North Tarrytown thought they were safe: The plant had survived earlier shutdown scares and the automaker recently spent millions of dollars to upgrade it.

They were stunned when word came Monday that the plant would close in 1995.

''We fought for this plant. We fought for the minivan. We're a really good plant,'' Manuel DaCosta, one of 3,456 workers, said after General Motors Corp. announced it would shut down two assembly plants - including the one here - and 10 parts factories by 1995.

''We thought we had a good plant and were doing a good job,'' said Richard Cariello, another worker.

''I live here in Tarrytown. Once they close here, this town will become a ghost town,'' United Auto Workers Local 664 President Donald Martino. ''I'm devastated. I can't believe it.''

The cuts are part of the plan to restore profitability to the huge automaker, which reported 1991 losses of $4.5 billion, the largest annual deficit in U.S. corporate history. GM announced in December that it would close 21 plants and lay off 74,000 workers by the middle of the decade.

The North Tarrytown plant was built in 1900 to produce Walker Steamer automobiles. Its closing will coincide with the retirement of the current generation of GM minivans.

The plant was recently retooled to produce the Chevrolet Lumina APV, the Oldsmobile Silhouette and the Pontiac Trans Sport.

Government and union officials have battled for years to preserve the plant on the Hudson River 30 miles north of New York. It once had a work force of more than 5,000.

In the early 1980s, GM threatened to close the plant, citing high utility costs and high taxes. But it stayed after the local government lowered the taxes, paid for training programs and got the plant a reduced electricity rate.

In return, GM built a $170 million paint shop, part of a $250 million investment to upgrade the plant and the centerpiece of a 10-year agreement state and local officials thought would keep the plant running at least through 1995.

William Regan, the city's administrator, said the GM plant paid $1.1 million in village property taxes last year, accounting for 20 percent of all such revnue.

''If it shuts down and nothing replaces it, there will be a serious effect on the area,'' he said.

Given the history of the plant and the far-off closing date, Martino said he held out hope the plant would stay open. But GM said there was none.

''This is final,'' said Darwin Allen, a spokesman for the automaker. ''North Tarrytown is not unique in having had the huge investment. It's not a matter of good plant versus bad plant.''