In the top of a double boiler, soften gelatine in cold water. Add beaten egg yolks and salt. Cook over simmering water, stirring constantly till gelatine dissolves and the mixture is slightly thick (about 5 minutes). Remove from heat. Stir in frozen lemonade concentrate. Chill until mixture mounds when spooned.
Beat egg whites and ½ cup sugar. Beat until stiff peaks form. Fold gelatin mixture into egg white mixture.
Whip cream. Fold ½ of it into filling. Put in baked, cooled 9” pastry shell. Chill until firm. Sweeten the rest of the whipped cream and use it to the top pie before serving.
Cream butter and sugar, add egg yolk, flour, and coconut. Pat mixture in pan. Chill 30 minutes. Bake 25-30 min. at 350 degrees