ran S edition onlyIt's never too early to teach a youngster the joys of fishing. Bob Stewart of St. Petersburg spent his day off Monday with his nephew, 3-year-old Joey Baker, casting for snapper near The Pier. Above, Joey watches intently as Stewart puts a worm on a hook. At right, the two fishermen lean over the sea wall waiting for a nibble. Below, with grim determination showing on his face, Joey reels in a fish.