In A Large Bowl, Beat Cream Cheese Until Smooth. Stir In The Shredded Cheeses, Mayonnaise, Garlic Powder, Onion Powder And Worcestershire Sauce. Shape Mixture Into Two Logs, About 6 In. Long. Roll In Pecans, Pressing Down Gently. Wrap Each In Plastic Wrap; Refrigerate For At Least 2 Hours Or Overnight. Serve With Crackers.