Chop 1 avocado, and place in a food processor; add Mayonnaise. Process until smooth, stopping to scrape down sides. Brush mixture over fillets. Stir together pistachios and next 3 ingredients Dredge fillets in mixture Place on a lightly greased 15x10 inch jellyroll pan. Bake at 450° for 12 to 14 minutes or until golden brown and fish flakes easily with a fork. Keep warm. Dice remaining 3 avocados and stir into Citrus Sauce. Pour over fillets and serve immediately.