SANTA ANA—Orange County District Attorney Todd Spitzer issued a stern warning May 27 to a pair of unidentified suspects sought in the road- rage shooting death of a 6-year-old boy on the Costa Mesa (55) Freeway in Orange, as the reward posted in the case swelled to $310,000. At a news conference in Orange, the county’s top prosecutor gave the woman and man who were in the car at the time of last Friday’s shooting of Aiden Leos 24 hours to turn themselves in. “We’re not messing around anymore,” Spitzer said. “So you choose door A or door B … Door A, we listen to what you have to say.” Door B, he explained, involved throwing the book at the killer and anyone who helped him evade justice. “You’ve got about 24 hours to turn yourself in or that door is closing on your future. I’m running out of patience,” …