A spy is in the Grammy camp, and it is none other than Grammy.com, the official Web site for Wednesday’s big music event from the Staples Center in Los Angeles. Tuesday’s report revealed what Madonna’s opening routine will be like, as previewed by her rehearsal. According to the site, Mrs. Guy Ritchie, who is reportedly back in fine physical shape, will roll onto the stage in a vintage stretch Cadillac that’s been detailed with the reflective mosaic finish of a disco mirror ball. She’ll then emerge from the backseat in full movie star regalia before stripping down to a tight leather jacket and pair of baggy, bell-bottomed jeans. (Meanwhile, behind the wheel of the limo will be petite rapper Lil’ Bow Wow.) From soul diva Macy Gray, expect a performance of her record of the year and song of the year nominee, “I Try,” before a quartet of giant, colorful video display. Paul Simon will sing “You’re The One,” from his album of the same name. The veteran musician has only one nomination this year, but it’s for album of the year. Should he win, it will mark Simon’s unprecedented fourth victory in the category.