In small saucepan, mix together gelatin and sugar. Slowly add 1 cup grapefruit juice, stirring until sugar is dissolved. Place on medium-high heat; heat to boiling, stirring occasionally. Remove from heat. Add remaining grapefruit juice, orange juice and orange peel. Chill until mixture mounds. When dropped from a spoon. Fold non-dairy topping into gelatin mixture and spoon into cooked pie shell. Chill.