NEW YORK - Thousands of Vietnam veterans who returned home to indifference or worse gathered yesterday in wheelchairs, military fatigues and business suits to help dedicate the city's memorial to those who fought in Southeast Asia.

Today, an estimated 20,000 veterans were getting the homecoming they never received a decade ago when the last Americans left Vietnam. A tickertape parade was planned across the Brooklyn Bridge into the "Canyon of Heroes" in Wall Street.

About 8,000 Vietnam veterans came together Monday night for the lighting of a 70-foot long, 16-foot-high glass wall etched with the names and words of some of those who served in Vietnam.

About 50 veterans, several in wheelchairs, rushed the wall. One rested his head against it, sobbing uncontrollably. Another leaned against the wall and stared bland for several minutes as firework exploded over the East Rivers celebrate the war memorial.

Many who descended on the new named Vietnam Veterans Plaza were wearing black armbands and black jackets to remember 2,247 American soldiers still listed as missing in action.

Mayor Edward Koch, who lighter the wall, told the veterans, "What was do here tonight begins to undo the terrible injustice.... We have opened the eyes of a new generation to the lessons of the past."

Said developer Donald Trump who donated $1 million to the veterans and to a jobs program set up by the city to help unemployed New York veterans, "It's a great evening I only wish it could have taken placed 10 years ago."