"To my mind," writer/director Paul Schrader said last week, "it's clearly the best script I've ever written." Schrader was sitting in his trailer on the Cleveland set of "Light of Day," a tale of family conflict and rock 'n' roll music then in its final days of shooting at a dingy rock bar -- but the script he was referring to wasn't the one he wrote for "Light of Day," or the ones he'd done for "Raging Bull" or "Taxi Driver" or the films he also directed, "Cat People" or "American Gigolo" or "Mishima."

Rather, Schrader was talking about his screenplay adaptation of Nikos Kazantzakis' "The Last Temptation of Christ," which Martin Scorsese was set to direct until, says Schrader, pressure from the Catholic and Protestant churches drove away all interested studios and financiers.

"I love that script, Scorsese loves it, and it's still his number-one priority," continued Schrader on a break during the shooting of "Light of Day," a film based on ideas he began writing and researching six years ago.

"But it's awfully hard. The French were gonna put some money in it, and they pulled out because, I hear, the pope himself called up the archbishop of Paris and said he heard a 'director of fame' was going to do this sacrilegious book."

If "Temptation" doesn't get off the ground, Schrader hopes Scorsese will shoot his script for the big-budget film "Gershwin" -- but that doesn't mean he's given up on the more controversial project.

"About 'Last Temptation,' I feel the same way I felt about 'Mishima' or this film," he said. "Sooner or later, as long as either Marty or I are alive, one of us will do it. There's gotta be a way to do it, even if it ends up becoming one of those 'Mishima'-like projects that's made to be put on a shelf."

Meanwhile, in a nearby "Light of Day" trailer, Michael J. Fox boned up on his guitar playing and talked about his next project, which will find him looking cleaner and acting funnier than he does in Schrader's gritty drama in which he sports longer hair and two left-lobe earrings.

"It's the complete antithesis of this film," he says of the comedy from "The Goodbye Girl" and "Pennies From Heaven" director Herbert Ross. "I mean, it's a good, old-fashioned, almost 1940s romantic quadrangle. It's about a kid from Kansas who goes to New York, and eventually resorts to nepotism. He hates to do it, but he's just beaten into smithereens." 0f Snake Previews

It's all terribly predictable: "Cobra" opened in a huge numbers of theaters and got savaged by the critics and made lots more money than any other film has made so far this year. But Warner Bros.' opening-day gimmick -- showing the film in around-the-clock screenings starting last Thursday, the day before the official opening -- may not have been an unqualified success, judging by Mann's Chinese Theater in Hollywood. The theater was just about sold out for the first screening, but after that business wasn't nearly as spectacular as expected.

The L.A. Herald Examiner, for one, was on hand counting heads, and it found that by the second "Cobra" screening the 1,500-seat theater was only a third full. The next performance -- at 2 a.m. -- drew only 200 fans; the 4 a.m. show attracted half as many; and by 6 a.m. the count was down to about half of that. What's worse, folks who braved those early-morning screenings reportedly didn't cheer when Stallone brandished his arsenal and snarled about how crime's a disease and he's the cure.