TAPPAN, N.Y. -- Early in 1964, Stanley Kramer's "It's a Mad, Mad, Mad, Mad World" was edited from its 193-minute premiere length to 154 minutes. Most of the moviegoers who helped make the comedy caper the second highest grossing film of that year never saw the 39 excised minutes. And with the whereabouts of that footage now unknown, moviegoers might never see them again.

Millions of Americans have somehow soldiered on nevertheless. And then there's Eric K. Federing.

His five-year campaign to make "Mad World" whole has rendered him -- in the words of a studio spokesman who's been on the receiving end of the bombardment -- "sort of a minor legend."

Federing publishes Mad World Update, which bills itself, incontrovertibly, as "the only newsletter devoted to the restoration and revival of Stanley Kramer's 1963 Cinerama comedy classic" (mailed free to 275 fellow fanatics). He arranges screenings each November (in New Carrollton last year, at an old Akron movie palace this fall) on the anniversary of the movie's opening at Hollywood's Cinerama Dome. Along with a network of contacts, collectors, moles and mavens he badgers studios, mines libraries and archives, buttonholes reporters and otherwise dedicates himself to the proposition that life remains incomplete without all 193 minutes of "Mad World." "Their efforts have been herculean," says a grateful Kramer.

"I'm not one to just start something and stop capriciously," says Federing. He is 27, an aspiring free-lance writer who shuttles between his family's home here in the Westchester suburbs and friends' spare rooms in Washington (where he practically camps at the Library of Congress). He says United Artists' attitude toward his jihad has been "cavalier." He is prone to understatement.

The fact is that through most of this quest, he and his allies not only failed to prod the studio into mounting a serious search for the missing footage, but failed to win any official acknowledgment of the gravity and urgency of this situation. Some of the early entries on Federing's mailing list, people who answered his notice in American Film a few years back, eventually lost interest. "Some people don't want to be in for the long haul," Federing acknowledges.

But there's heartening news for the stalwarts: An anonymous but not powerless United Artists executive -- who, like Federing, saw the movie as a kid and still cherishes it -- will seek corporate approval for a search of labs and storage facilities to see if the original, uncut 70-mm print still exists. After years in which most of the studio people Federing contacted were, as the executive admits, "more worried about the new James Bond movie," the Mad World campaign has a confederate on the inside.

Odds of finding the missing minutes, according to the studio spokesman, are "decent, not overwhelming." "Not any worse than 5 to 1," estimates Kramer, whose own inquiries have yielded no fresh leads.

Federing doesn't want to hear it. "No; it's around," he insists. "If for whatever reason the studio junked it, collectors haven't. If it's not in the U.S., it's certainly overseas." He suspects it's in a salt mine-turned-film-storage-vault in Hutchinson, Kan. "People I've been in contact with suggest it's there," he says mysteriously. "There are boxes."

And what will the film archeologists see if they unearth the complete negative? "Mad, Mad, etc." featured a genuinely all-star comedy cast -- it was Jimmy Durante's last movie, not to mention Zasu Pitts'. Its reviews were mixed: The New York Times' Bosley Crowther called it "wild and hilarious all the way," while Hollis Alpert of Saturday Review demurred, writing "the question is, is it funny? And the answer is, sometimes." The Washington Post's Richard Coe also was unenthusiastic -- "but of course, he didn't see the whole picture," Federing points out.

Federing & Co. know from the shooting script, publicity stills and other clues they've amassed that the omissions include:

A Jonathan Winters monologue;

Pratfalls by Ethel Merman;

Most of Buster Keaton's scenes as Jimmy the Crook;

Scenes of Dick Shawn, as the manic beach bum, stealing Barrie Chase's car;

All of Stan Freberg's lines and all of Howard Da Silva's scenes;

The film's overture, exit music and sporadic "news bulletins" that enlivened intermission with reports of the characters' converging on the stolen loot;

Various gags and goofs by the likes of Phil Silvers, Milton Berle, Buddy Hackett, Sid Caesar, Edie Adams, Spencer Tracy, et. al.

"I supposedly had the creative say-so," Kramer recalls. "Unfortunately, we were operating under the rules of the distribution company."

The cuts, made over his objections, occurred when the Cinerama spectacular was transformed into ordinary 35-mm prints for general release. "Those theater owners wanted to fit in as many shows as they could," Federing explains, trying to modulate his contempt. "They needed a shorter film. They wanted to sell as many tickets and as much popcorn as they could."

Along with his "dedication" (the description he prefers to "obsession"), Federing has the distaste for the modern world one would expect from someone a half-century older. Nothing is as good as it used to be. Small movie screens are inferior to the big ones of yore. Videocassettes are inferior to theatrical showings. A '61 Plymouth Belvedere has it all over a Toyota Corolla. Old movie theaters continue to be demolished, unconscionably, for unglamorous sixplexes. Even the restored art deco palace that is Radio City Music Hall is tarnished, for Federing, by the T-shirt hawkers outside.

As for the 154-minute "Mad World," he says, "editing has destroyed the theatricality of the movie ... You can still enjoy the picture on one level, but when you know what's missing, it's annoying as hell."

"Mad World" is only one small example of Hollywood's profligacy, he points out. Scores of silent movies; chunks of '60s epics like "The Alamo" and "Spartacus"; a Marx Brothers movie that was never released -- all are missing. It makes him a bit morose. "What bothers me more than anything is this attitude that even when something works, you keep tinkering with it and make it new-and-improved until you destroy it," he complains. "Everything seems to be temporary. If anything survives, it's nothing short of a miracle."

Federing's reverence for the showmanship of the past will almost certainly provoke another round of lobbying even if United Artists does restore "Mad World." The U.A. confederate, understandably, is thinking in terms of reducing the 70-mm negative, if it exists, to 35-mm prints for general release, with possibilities for cable and cassette distribution. Each 35-mm print, he points out, would cost about one-tenth as much as the estimated $25,000 required to make a new 70-mm print.

Whereas Federing is fantasizing about a full-bore restoration, in 70-mm with six-track sound, shown for limited, hard-ticket engagements at selected, preferably elegant, theaters.

He can see it happening next year, in fact, in time for the movie's 25th anniversary. The premiere will be back at the Cinerama Dome, with searchlights and maybe red carpets. Friends have suggested that he should enter with Katharine Hepburn on his arm, but Federing is more concerned that the cast people be there, "those that are still with us. And the crew people who worked on the film, whose names I still don't know ... Just an evening, plain and simple, to have a good time and pay tribute to the film and know that it's going to be around."

As at the 1963 premiere, Federing thinks, everyone should wear black tie. "I'd like to do it right," he says. "No orange hair, preferably."