Given what happened in Chatsworth, it might be difficult for Nick Williams to hold fast to his own innocence. Perhaps that's why he jettisoned Doglover1000 for Amtrak458an identity unburdened with the weight of the Metrolink crash. Still, one wonders how long it will be before the pull of girls and cars and college draws him away from his model railroad. Who can say? The Fullerton crew, who stare now, wide-eyed, as the holiday train slowly moves north, haven't let growing up get in the way of their fun.