Oven temperature 425F Scrub the quahogs under cold running water to remove any grit from the shells. Add water to a large pot to a depth of about 1 1/2 inches. Add a splash of dry white wine, if desired. Bring to a boil over high heat: add the quahogs, cover the pot, and lower the heat to medium. Cook for about 5 minutes, or until the quahogs open. As they open, remove from the pot with tongs and set aside to cool. When all are removed from the pot, return the heat to high and boil the broth, uncovered, for about 3 minutes to reduce it, and intensify the flavors. Remove from the heat, strain through a fine mesh sieve lined with 2 layers of dampened cheesecloth, and set aside. When the quahogs are cool enough to handle, remove the meat and chop it, saving the shells. Set aside. Place the oil and butter in a large skillet set to medium. When it sizzles, add the onion, garlic, celery, pepper and thyme. Cook, stirring occasionally, until the mixture is tender and fragrant, but not browned. Lower the heat and add the breadcrumbs, and stir until evenly combined. Remove from heat and transfer the mixture to a large bowl. Add the chopped quahogs, parsley, lemon juice, worcestershire sauce, and salt and pepper to taste. Mix well. Add the beaten egg, and moisten as needed with the reserved broth. Form spoonfuls of the quahog mixture into large meatball-sized balls. Place in one half of a quahog shell, and flatten (the shell should be full). Place the stuffed shells on a cookie tray. At this point, you can cover the tray with plastic wrap and refrigerate (up to overnight) until you are ready to cook the stuffies. Bake in a preheated oven for about 15 minutes, or until piping hot with a browned top. Serve immediately, with lemon wedges.