Fettuccine with Spicy Shellfish

Name: Fettuccine with Spicy Shellfish
Ingredients: 1/2 cup extra-virgin olive oil; 1 teaspoon crushed red pepper; 1 pound fresh fettuccine; 1/2 cup freshly grated Parmigiano-Reggiano cheese; 1/4 cup shredded basil leaves; 6 ounces dry chorizo, quartered lengthwise and thinly sliced crosswise; 1 large shallot, minced; 2 large garlic cloves, minced; 2 plum tomatoes—peeled, seeded and chopped; 1 dozen littleneck clams, scrubbed; 1 cup bottled clam juice; 1 pound mussels, scrubbed; 1 pound shelled and deveined medium shrimp; Salt