Preheat your oven to 325 degrees F. Spray a 2-quart baking dish with cooking spray.
Whisk together mayonnaise, Worcestershire sauce, lemon juice, Old Bay Seasoning, and half-and-half in a large bowl.
Using a large spoon, gently stir in crab meat, stuffing mix (2 ½ cups), onion, and celery until combined.
Transfer crab mixture to the prepared baking dish and spread evenly.
Prepare the topping: Place stuffing (1 cup) in a medium bowl and drizzle with melted butter. Toss to coat as evenly as possible.
Sprinkle buttered stuffing mixture over crab mixture as evenly as possible.
Bake for 45 minutes, or until set and heated through.