Pick through crab to remove any shell, leaving large lumps intact. Place in a bowl with the lobster meat. In a separate bowl, mix together egg, mayonnaise, mustard and celery salt. Add to lobster mixture and toss well, trying to not break up crabmeat. Sprinkle 1/4 cup panko over mixture and mix well. Refrigerate for 15 minutes. Form into 4-oz. cakes and roll in remaining panko until well coated. Refrigerate until ready to cook. Heat olive oil in sauté pan. Over medium heat, brown cakes on one side, approximately 2 minutes. Flip cakes and place in 400-degree oven for approximately 5 minutes, or until heated through.