If at 31 Johnny Bench is on the old side for a catcher, he's young to be packaging the story of his life: all the punch lines so far are on record. But back in 1968 when he was named Rookie of the Year, he ""realized the potential for selling myself to the public,"" and he's proud of being smart enough to cash in on his fame before it fleets. The Reds signed Johnny Bench right out of his Oklahoma high school; he hit Cincinnati with superstars in his eyes after two terms in the minors and won every big title in baseball early in his career. Bench is still ""bothered,"" however, that Sparky Anderson made Pete Rose team captain, and still ""bugged"" that Brooks Robinson got the Hickok Belt Award in 1970: Bench took both MVP and Major League Player-of-the-Year honors that season, but he always ""wanted it all."" He hobnobbed with Bob Hope and, in 1975, invited President Ford (and 899 others) to his wedding; Bench will not talk about the short-lived marriage itself and he makes something of an issue over his reticence. But he doesn't apply it to the one-night sexual ""scores"" he racks up ("". . . we went back to the condominium. . .""). Also unexpected is a preoccupation with mortality that Bench dates from the separate accidental deaths of five of his schoolmates and carries through his own scare by a lung-spot (benign) and beyond, to his work with the Cancer Society. He winds up with a visit to his grandmother, but even that fails to bring out the nice guy in Johnny Bench, who was hot enough to play professional baseball not when he grew up, as he'd dreamed, but before; maybe he still hasn't had a chance.