Fruited Lemon Gelatin Salad

Ingredients
1 (6 ounce) package lemon gelatin
2 cups boiling water
1 (12 ounce) can lemon-lime soda
1 (20 ounce) can crushed pineapple
1 (15 ounce) can mandarin oranges, drained
2 cups halved green grapes
1 egg
1/2 cup sugar
2 tablespoons all-purpose flour
1 tablespoon butter or margarine
1 cup heavy whipping cream, whipped
Lettuce Leaves
Directions
1. Dissolve gelatin in boiling water. Stir in soda. Refrigerate it till partial set. Drain pineapple, reserving juice and keep pineapple aside. Add water to pineapple juice, if necessary to make 1 cup. Stir pineapple, oranges and grapes into gelatin. Pour into a 13-in. x 9-in. x 2-in. dish. Refrigerate.
2. In a saucepan over medium heat combine egg, sugar, flour, butter and remaining pineapple juice. Bring to a boil, cook and stir for 2 minutes until thickened. Cool completely. Fold in whipped cream. Spread over gelatin. Refrigerate until firm. Cut into squares and serve on lettuce if desired.