A dead man played Broadway this week and brought down the house. Three standing ovations. Men yelling "bravo". Women running down the aisles to the stage. Tears. Screams.

Of course, they were screams for Elvis. Live. At least that's what the marquee at the Palace Theater said: LIVE ON STAGE/ELVIS THE LEGEND LIVES; then in smaller letters, to the side: starring Rick Saucedo.

It was so easy to pretend. Why there, onstage, in the 1,300-seat theater, was Elvis' longtime drummer, D. J. Fontana, and there, under the 15-foot-high Elvis slides they kept flashing all around, was Elvis' old backup group, the Jordanaires. And stage center, carrying the show, singing 30 Elvis hits, dressed Elvis clothes, walking like Elvis, talking like Elvis, was Elvis-sound-alike Rick Saucedo, though Rick's name was never mentioned during the show.

"Introducing Elvis Presley," the announcer yelled, when Saucedo came on, and the audience, which had paid from $9.50 to $13.50, was more than happy to go along. They screamed even before "Elvis" stepped out onstage, screamed throughout the scene where "Elvis," opposite an Ed Sullivan imitator, appeared on the Sullivan Show. They also screamed at the climax of the show when "Elvis" sang, "I Did It My Way," before disappearing in a dry-ice puff of clouds, after which the band played "Glory, Glory Hallejuiah."

The mood at the performance was so pitched that when "Elvis" mopped his face with a towel and threw it to the crowd, they grabbed for it. The fantasy was so intense, they look Instamatic pictures, "Long live the King!" they yelled, and "Elvis, Elvis!" at Rick Saucedo. Nobody yelled "Rick".

The king may be dead, but his imitators are doing just fine. One mimic, Alan Meyer, reportedly grossed nearly $1 million last year, another, Dennis Wise, of Ocala, Fla., has just had plastic surgery done to make him appear more Elvisonian. (The bandages come off next week, as a weary nation waits.) But the local king of the kings of imitators is Saucedo, a 22-year-old poor boy from Chicago, who opened Tuesday, after about only a week of mostly radio and late-night TV promo, to a near-capacity crowd.

What made the producers sink a reported $250,000 in a show constructed around an imitation? Reality.

"Our offices are right next door to "Beatlemania," the show which has run about nine months (with Beatle imitators)" said one of the show's three producers, John Finocchio. "That gave us the original idea. And then we did some research and found that since Elvis' death there has been an episode - I mean literally in everything having to do with Elvis. There are hundreds of thousands who seriously mourn Elvis and would give anything for one more opportunity to see him - 83 percent of our seats here sold out in the first week - and this show can fulfill a tremendous need. We decided to do a show that would be in good taste, an honest tribute.

"Hey, I said tribute, not charity," says Finocchio.

"Not that there's anything wrong with that. This country was built on capitalism.And no, we don't think it's exploitation. Any impersonator makes his living imitating other people, look at Rich Little. And of course, we are doing it in good taste. No, we don't mention drugs because we have no proof that Elvis was a drug addict. And besides, the man is dead."

The search for the right Elvis for the show, as Finocchio tells it, took three months, during which Finocchio and his partners saw '30 or 40 Elvises all over the country - God knows how many are really out there." They finally settled on Saucedo, who had been playing Presley for the past five years, and was, at the time of his discovery, doing a concert in Winnipeg. Speaking of his star, Finocchio beams like a man in love. "No one else could shine this boy's shoes," he says, comparing him to other imitators.

Saucedo, onstage, sounds eerily like Presley, though he is baby-faced and two inches shorter and a lot less heftier. Saucedo also works at Elvis' mannerisms, his shakes and grinds, and though he lacks Presley's bite, he does a good rock 'n' roll show.

But offstage, the bravado goes, the resemblance fades. Soft-spoken, shy, Saucedo - whose father is a maintenance man and whose mother works in the Curtis Candy factory - curls up in a seat in the empty theater and stirs and restirs his coffee. He wears a gray sweatshirt, jeans, and Converse All-Stars; a medallion presented by an Elvis fan club when he played at Elvis' birthday party last month ("It was in Memphis - I was sure they were going to hate me there"), and an ornate gold ring.

He says he's been involved with music since the age of 12, when he went to a wedding and "saw all the girls going up to the stage where the band was." He says he's been doing Elvis ever since the time, prior to doing "Hound Dog" with his own band, he slicked back his hair and the crowds went wild.

He declined discussing salary. "When you start seeing dollar bills in front of your eyes, you're gonna drop. I'd rather think about the music, that's why I'm here." When nudged, he said that what he would like to do with the money was to buy a house for his parents, his 1-year-old sister, and his older brother, a 23-year-old factory worker.

His sister's name - though this information will not come from Saucedo - is Lisa Marie, which, not coincidentally, is the name of Elvis Presley's daughter. Saucedo insists he never thinks of himself as Elvis, but somewhere, especially onstage, where he performs in a silver belt with the name Lisa Marie on it, the identities blend.

The blended well enough Tuesday night for about 1,500 fans, including Mrs. Barbara Bursich, the secretary of the Kankakee Chapter of the Rick Saucedo fan club, who had traveled from Illinois to New York especially for Saucedo's opening.

Mrs. Bursich, who gave her as 42 - "The same age as Elvis, though he just turned 43" - said she had seen Elvis seven times in Las Vegas. (I got him to kiss me there, too . . . I had it just as bad as you can get it." She distinguished, in a whisper, between Saucedo and Presley. "Ricky seems more humble; Elvis got sort of big-headed toward the end, and I think Ricky is more tender-hearted.

Ray Walker, a member of the Jordanaires, the group which appeared with Elvis on his records and in his 28 movies (and a group, in which each member reportedly makes about $65,000 a year doing backup work in Nashville) swears the Real King wouldn't have minded one bit.

"The idea of making money from him, that was Presley's idea of a gift to the ones he'd leave behind," said Walker. "These guys who are initating him, he didn't care. Once one of them walked into a club where Elvis was, dressed like Elvis, and you know what Elvis did? He just grinned and gaave him the thumbs up.?