Cut watermelon into a basket. Melon ball the fruit out of all the pieces. You will need about 4 cups of balls and save the rest for another use. In a large bowl, combine fruit cocktail, oranges, cherries, pineapple, marshmellows and watermelon balls. Add soda, toss lightly. Cover and refrigerate until chilled. (about 2 hours) Just before serving, stir in coconut and spoon into the basket.