Grate the orange; set peel aside. Separate the orange into sections. cut three of the sections into quarters; set aside for later use. Cover and refrigerate remaining orange sections for snacking or other use.
Beat cheeses, sugar and vanilla in a large mixing bowl on medium speed until well blended. Add the orange peel and chocolate; mix well. Gently stir in 2 cups whipped topping.
Spread 2 cups of the cheese mixture onto bottom of 13 x 9 baking pan. Top with 30 wafers; cover with 1 1/2 cups of the remaining cheese mixture. Top with the remaining whipped topping; cover. Refrigerate 4 hours.
Top with the quartered orange sections and remaining five quartered wafers. cut into squares. Store leftovers in the refrigerator.