Slice the citrus into medium sized circles. Remove skins after slicing. Remove any seeds visible. Align citrus circles starting with the darkest color in columns of two. I went from oranges, to tangerines, to grapefruit and ended with lemon. Set aside.
Glaze and Citrus
Line a 9 inch baking dish with parchment paper. Then, in a medium sauce pan, add all ingredients and simmer for 3-4 minutes. Transfer glaze to baking dish, spread evenly. Next assemble the citrus on top of the glaze starting with oranges ending with lemons.
The cake
Preheat oven to 325 degrees. In a large mixing bowl, using an electric hand mixer, combine all of the ingredients. Transfer cake mix on top of citrus and glaze. Bake for 45-55 minutes or until a toothpick inserted into the middle of the cake comes out clean. Allow cake to completely cool. Then invert cake onto cake board.