GOOD MORNING: A very busy Martin Scorsese took time away from the final mix of “Gangs of New York” to talk to me about the film — and the dual bow of Leonardo DiCaprio-starring movies within a week of each other at Christmas. (The other is Steven Spielberg’s “Catch Me If You Can” for DreamWorks.) Harvey Weinstein wants to open “Gangs” Dec. 25, but Scorsese would like to go Dec. 20. “Harvey wanted to go Christmas 2001,” Scorsese laughingly reminds. Scorsese is mixing the final sequences and expects to be completed in “a few weeks,” with an answer print in four. “I’m working on reels eight and nine,” he said, “and it now runs two hours and 40 minutes without the credits.” He believes the cost of the film is “in the 90s” (but others put it considerably higher). Martin started the project in September 2000, wound filming in April 2001 and took a two-month break. He reminds he took the same amount of time and care on “Goodfellas.” The giant New York-in-the-1850s set at Cinecitta remains up and he says it’s become a tourist attraction, as well as an attraction for would-be producer-directors of quickie movies! He’d often shoot three units on that stage, tramming from one to another. George Lucas marveled at the set when he visited during production. When Scorsese visited Lucas recently at Skywalker to see his demonstration of new technology, they posed for a picture together. “He labeled us ‘The Old’ and ‘The New,’ ” laughed Scorsese, who prefers to capture his actors’ emotions on film cameras rather than digital. “Even when I’m looking at the video monitor on the set,” he admits, “I often have to go on the set to see the emotion on the actor’s face — which the film cameras will capture.”WHAT IS THE MESSAGE of “Gangs of New York”? Scorsese responded: “ ’What is America?,’ it asks. It proves that America is still defining itself. Back then it was the Irish who were coming here off the boats. And it was the Anglos who didn’t want them.” Prejudices continued through the years. Scorsese still wants to make a film on a similar subject, about Italian immigrants — with personal input about his family’s beginnings here. He has a script from Nick Pileggi, but “I need a bit of rest” before tackling this one … Music will be an important part of “Gangs.” The sound, along with the picture, will help re-create the world of the 19th century. To create this music he has to date set the talents of Elmer Bernstein, Peter Gabriel and Bono … Scorsese had boundless praise for his cast, headed by DiCaprio, Cameron Diaz, Daniel Day-Lewis and Liam Neeson. He plans to reteam with Leo early next year with “The Aviator” for WB (domestic) and Initial Entertainment Group (foreign). It’s the story of the young Howard Hughes in Hollywood. John Logan is scripting. As he’d re-created old New York for “Gangs,” Scorsese plans to re-create old Hollywood for this epic … As for the strategy to get Leonardo to publicize each film, both camps acknowledge it’s no secret the young star is publicity-shy (to say the least). But they are confident he will respect both filmmakers, Scorsese and Spielberg. As for DiCaprio’s co-star in DreamWorks’ “Catch Me If You Can,” Terry Press puts it succinctly when she says, “I wish Tom Hanks would give lessons in how to be a movie star.” THE KENNEDY CENTER HONORS add royalty to their list this year: Dame Elizabeth Taylor and Sir Paul McCartney will be among the five to be toasted Dec. 8 in Washington. As is customary, the president and first lady salute them with a reception in the White House preceding the center’s show (produced by George Stevens Jr. and Don Mischer). On Dec. 7, Secretary of State Colin Powell and his wife, Alma, will uphold the tradition of hosting the honorees for dinner in the State Dept., where the medals are bestowed … At their final L.A. dinner before departing for London and Sweden, Liza Minnelli and David Gest dined at Trader Vic’s, where they told me of plans for a Christmas show. It will be taped Dec. 5-6 at N.Y.’s Town Hall for airing Christmas 2003 … Irv Kupcinet celebrates his 90th birthday Wednesday. He’s also celebrating his 60th year columning for the Chicago Sun-Times … David Raksin, who celebrates his 90th Aug. 4, will get a one-hour tribute on KCRW, 3-4 p.m. … Another music legend, Engelbert Humperdinck, will be honored Oct. 11 at the BevHilton by the Associates for Breast & Prostate Cancer Studies. Proceeds fund the John Wayne Research Center … The Nov. 20 Environmental Media Assn. honors TV and films at the Wilshire Ebell. Toyota sponsors; the feed that follows is a totally organic menu … Now that Lance Armstrong’s won his fourth Tour de France, I wondered if Bud Greenspan and Ed Pressman will go ahead with plans for their biopic. Greenspan notes Armstrong’s story has received so much play in all the media, he wonders about going the screen route. “I thought it would be a great story if only being able to go to the starting line of his first race after beating cancer.” Greenspan added, “I still think it’s the greatest story in sports” … “Don’t Let Go” writer-director Max Meyers, who won best feature at the Westchester, N.Y., fest, will receive a Special Achievement Award at the Stoney Brook, Long Island, fest.