It’s been a long time since Frankie Muniz was “Malcolm in the Middle.” These days, he’s more like “Malcolm in the Front.” The multitalented actor-turned-race car driver is leading the standings in the ARCA Series, one of the lower rungs on the NASCAR feeder system, through the first three races in his first full season. His goal is to reach the Cup Series eventually, but the 37-year-old Muniz harbors no misconceptions about just how difficult it will be to climb that ladder.