Preparation Put oven rack in middle position and preheat oven to 350°F. Sprinkle coconut in 1 layer in a shallow baking pan and toast, stirring once or twice, until evenly golden, 8 to 10 minutes. (Watch carefully; edges burn quickly.) Meanwhile, cover chicken with cold water in a 2-quart saucepan and simmer over moderate heat until just cooked through, 10 to 15 minutes. Remove chicken, discarding cooking liquid, and, when cool enough to handle, shred into 1/2-inch-thick pieces in a large bowl. Cut peel, including most of white pith, from pummelo with a sharp knife. (Peel is very thick.) Using your hands, split pummelo from center of one end, like an orange. Pull off interior pith and remove segments 1 at a time, then remove segment membranes and any small seeds, separating pulp. (Fruit may remain in small clumps.) Add pummelo pulp to chicken. Grind dried shrimp into small pieces in grinder, about 20 seconds. Heat a dry 8-inch heavy skillet over moderate heat, then cook dried shrimp, shaking skillet, until pale golden, 1 to 2 minutes. Transfer to a small bowl. Whisk together lime juice, fish sauce, sugar, coconut cream, toasted coconut, chiles, and 1/8 teaspoon salt in a small bowl, then stir into pummelo mixture. Halve jumbo shrimp lengthwise with a sharp large knife, leaving shells in place. Devein, rinse, and pat dry. Season with remaining 1/8 teaspoon salt and dredge in rice flour, shaking off excess. Heat 1 inch oil in a 4- to 6-quart pot over moderately high heat until it registers 375°F on thermometer. Fry shrimp in shells in 2 batches until golden, about 3 to 5 minutes per batch, returning oil to 375°F between batches. Transfer to paper towels to drain. Serve pummelo salad topped with fried jumbo shrimp (peeled if desired) and sprinkled with toasted dried shrimp. *Ingredients available at Asian markets, ethnicgrocer.com (866-438-4642), and templeofthai.com (877-811-8773). Cooks' note:You can reuse the shrimp frying oil for the Fish with Red Curry Sauce. Cool the oil slightly then pour through a fine-mesh sieve.