Muralist's take on Andy Warhol's Marilyn Monroe is almost done. Really.

The Andy Warhol show is up. It opened Oct. 20 at The Art Institute of Chicago.

The huge Warhol mural on North Michigan Avenue publicizing the show, though, is not quite up.

Jeff Zimmerman is working as fast as he can.

"Just a lot of moving parts," he says. "The city, the alderman."

Plus: the weather. Pesky OSHA concerns. And the river of pedestrians walking directly underneath him. Care is required.

"Michigan Avenue is right there," he says. "A million people walking by, and I have not dripped on anybody."

Then again, Zimmerman is facing a much bigger challenge than Warhol tackled when he took a publicity still from the Monroe movie "Niagara" and silk-screened it.

You can't silk-screen a wall. The surface at 663 N. Michigan Ave. is 70 feet by 70 feet - nearly 5,000 square feet, a little bigger than an NBA basketball court. It's also 150 feet in the air.

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