Heat the oven to 375 degrees. Butter a 2-quart baking dish In a large mixing bowl, beat the eggs with salt to taste (I suggest about 1/2 teaspoon). Add the grated sweet potatoes and the apples. Pour the lime juice over the grated apples and sweet potatoes, then stir everything together. Combine the honey and 2 tablespoons of the melted butter and stir together, then toss with the sweet potato mixture and combine well Transfer the mixture to the prepared baking dish. Cover the dish tightly with foil and place in the oven. Bake 45 minutes. Remove the foil and brush the top of the kugel with melted butter. Return to the oven and bake for another 15 to 20 minutes or longer, brushing every 5 minutes with butter. The kugel is ready when the edges are browned, the top is browned in spots and the mixture is set. Remove from the heat and allow to cool for 10 to 15 minutes before serving