Beat egg yolks until lemon colored.Add salt and maple syrup. Cook in top of double boiler until yolk mixture thickens.Cool. Beat egg whites until stiff.Combine maple mixture, egg whites, and 2/3 of the Kool Whip, using a folding motion.Fold in 3/4 cup of the nut meats.Scrape into baked pie shell.Cover with remaining whipped topping.Sprinkle with remaining nut meats and chocolate shavings.Freeze for a minimum of four hours.