1Heat oven to 350°F. In 15x10x1-inch pan, place cake cubes in single layer. Bake 15 minutes, turning once, until toasted.
2In large bowl, beat cream cheese, 1/2 cup of the sugar and the sour cream with electric mixer on medium speed until well blended. Gradually add milk, beating until smooth.
3In medium bowl, beat sweet potatoes, vanilla, salt and remaining 1/4 cup sugar with electric mixer on medium speed until smooth.
4In trifle bowl or 3-quart glass bowl, layer one-third of the cake cubes and sour cream mixture. Top with half of the sweet potato mixture and 1 tablespoon coconut. Repeat layers once. Top with remaining cake cubes, sour cream mixture, coconut and the pecans. Repeat layers once. Sprinkle with remaining 1 tablespoon coconut and the pecans. Cover; refrigerate at least 1 hour.