m., police said. Callea, 33, of Buffalo, was unarmed but had the unloaded shotgun and four shells in his nearby parked car. "I'm going to kill him," Callea told Stern's driver. While bodyguards ushered the K-Rock radio star to his studio, the limo driver followed Callea back to the suspect's car, parked on Madison Ave. A bodyguard flagged down two city deputy sheriffs on towing duty. Deputy Sheriffs Steven Calzati and Nick Dousmanis radioed city cops and asked Callea if he was armed. "I have a shotgun in my trunk," the sheriffs said Callea replied. They found a rusty, 16-gauge, single-barrel shotgun and four rounds of ammunition in the front passenger seat. The weapon had been stolen in Jacksonville, Ill., but it was not clear how Callea obtained it. "He kept saying all he wanted was an autograph, and that Howard knew who he was and was expecting him," Calzati said. "He seemed like he might have been a little high," Dousmanis added. Capt. Glen Kotowski of the Midtown North Precinct said Callea drove to the city several days ago. He said it was not clear if the sole purpose of his trip was to confront Stern. The suspect's brother, Joe Callea, called him an "idiot.