READING, PA—Miguel Martinez, 48, who immigrated to the U.S. 30 years ago, last week lost his leather-cutting job at GST AutoLeather, Inc. to his 66-year-old father Roberto. "I came to this country in 1974 to make a better life for my family," Martinez said Monday. "But in December, they moved the factory where I've been working for 22 years down to Nuevo Laredo, Mexico. I love my father, but that goddamn beaner stole my job." Martinez's $18-an-hour duties will now be performed by his father for $7 a day.