While Jake LaMotta’s “Raging Bull 2” faces a legal fight from MGM, the boxer’s launching a stage show and a new documentary on his life. We’re told the pugilist, who turns 91 Tuesday, was just released from the hospital after falling and rupturing his pubic bone, but his doctors have cleared him for an off-off-Broadway run of his “Lady and the Champ” starting July 19 at the Richmond Shepard Theatre. Meanwhile, director Carl Shimkin has trailed his every move the past year-and-a-half for a doc, “Moving Forward, the Untold Story of Jake LaMotta.” Jake’s younger future seventh wife, and fiancée of 14 years, Denise Baker, co-stars in both projects, and directs the live show about LaMotta’s career and colorful love life. MGM’s moved to shut down production on a sequel to Martin Scorsese’s classic. The studio said in a complaint Tuesday that LaMotta doesn’t have the rights to make a sequel with William Forsythe playing him. When we asked about the “Bull” suit, LaMotta, ever the showman, told us, “If you want to know the real story, come and see my show.”