Seventeen years after his death, blacklisted screenwriter Michael Wilson is getting credit for having co-written one of Hollywood's most highly regarded films - "Lawrence of Arabia."

From the date of the film's release in 1962 until now, Robert Bolt, the acclaimed British playwright, has been the only writer credited with creating the script, which was nominated for an Academy Award in 1963.But the Writer's Guild of America has now determined that Bolt must share the writing credit with Wilson, according to officials of the guild, who said that documents in the union's possession confirm Wilson's role.

Wilson, blacklisted after he appeared as a hostile witness before the House Un-American Activities Committee in 1951, contended until his death in 1978 that he had been denied the co-writer's credit because of the power the blacklist retained, even in the early 1960s. Bolt and the film's director contended that they had not based the final screenplay on Wilson's original 273-page script.

But the Writer's Guild, which has the final say in determining screenwriting credits on films, has found that Wilson contributed more than enough to the original screenplay to earn a co-writing credit. The union is urging Columbia Pictures to change the writing credits on all future prints, videocassette releases and laser disks.

Since 1980, the guild has been pursuing the goal of restoring credit to blacklisted writers, who often worked anonymously or under assumed names during the 1940s, 1950s and early 1960s. In recent years the guild has determined that writing credits had been improperly withheld from Dalton Trumbo, for the screenplays of "Roman Holiday," "The Brave One" and "Gun Crazy," and from Albert Maltz for "Broken Arrow."

The posthumous writing credit was Wilson's second. In 1984, while the guild was investigating the credit issue, the Academy of Motion Picture Arts and Sciences recognized Wilson and blacklisted writer Carl Foreman as the writers of "Bridge Over the River Kwai" and presented their widows with posthumous Oscars.

Wilson had been the original writer hired by producer Sam Spiegel to write "Lawrence of Arabia," and in 1960, director David Lean sent Wilson a telegram praising an early draft of the screenplay.

"What a masterly job you are doing," Lean told Wilson. "Your extraordinary grasp and inventive appreciation of complex subject and character fills me with admiration and excitement."

A few months later, however, the collaboration collapsed, and Wilson quit the project after submitting the third draft of his screenplay. Bolt was hired to replace him. Until his death, Wilson maintained that the film's basic characters and plot were his own creations, and that Bolt was only responsible for the dialogue.

"If I were `clean,' " Wilson told Bolt in a letter dated Nov. 29, 1962, "my name would already be alongside yours as co-author of this picture." By "clean" he meant not blacklisted.

Lean and Bolt, however, maintained just as adamantly, until their deaths, that they did not rely on Wilson's original scripts. This position was rejected by the Writers Guild of Great Britain in 1963 when it awarded a shared writing credit to Bolt and Wilson. Spiegel, an American, chose to ignore the British ruling.