DAILY NEWS: AT 4:15 A.M., “Mr. Cheng” gets a call on his cell phone, signaling him to head outside to the light-blue van that will take him and other illegal workers to a mail-packaging factory in Montgomery County, to jobs that pay just above the minimum wage. It’s dark and quiet on the streets of South Philly as the van drives around, picking up other workers, who greet each other in Indonesian. Cheng is ethnically Chinese, but was born in Indonesia and lived there until he came to the United States about eight years ago. “I was dreaming of a better life,” he says, when asked why he came here — and stayed. Cheng (not his real name) is one of the estimated 103,000 illegal immigrants living in Philadelphia and its four suburban counties — who often live in the shadows, working low-paid jobs, with the fear of deportation as they try to make a way for themselves here. This is his story — an inside glimpse into how one illegal immigrant has been surviving in the city. MORE