SANTA CLARA, Calif. (AP) — Brett Favre vs. Steve Young. Aaron Rodgers dueling with Colin Kaepernick. The catch by Terrell Owens, electrifying returns from Desmond Howard and breathtaking runs by Kaepernick. Few franchises have been as intertwined over the last quarter-century as the Green Bay Packers and San Francisco 49ers, with coaches getting groomed in one spot and ending up in the other,…