Preheat the oven to 375°F. Using a handheld or stand mixer, beat the softened cream cheese in a large bowl on medium-high speed until it becomes smooth and fluffy, about 1–2 minutes. Incorporate the sour cream and mayonnaise into the whipped cream cheese, blending on medium-high until thoroughly mixed. Add the dry mustard, lemon juice, shredded cheddar cheese, Old Bay seasoning, and Worcestershire sauce, mixing again until fully integrated. Carefully fold in the lump crab meat with a rubber spatula, ensuring the meat remains intact while evenly distributing it throughout the mixture. Spoon the prepared dip into a large baking dish or divide between two smaller ones. Sprinkle the reserved cheddar cheese over the top, and if desired, garnish with chopped Italian parsley or an additional dusting of Old Bay. Transfer to the oven and bake for 30 to 35 minutes, or until the dip is heated through and bubbling around the edges, ensuring it reaches an internal temperature of at least 165°F. Serve hot alongside chips, or crisp celery and carrot sticks for dipping.