Shuck clams from shell. Clean shells thoroughly. Place each clam onto a clean 1/2 shell; set aside.
Preheat broiler for medium heat.In a large skillet, cook 6 ounces diced bacon over medium-high heat, stirring, until fat has rendered and bacon
is browned and crisp, about 7 minutes. Lower heat if skillet gets too hot and begins to smoke.
Stir in bread crumbs and Parmesan to evenly coat in bacon fat and cook, stirring and tossing, until bread crumbs are lightly toasted, about 3 minutes.
Transfer to a bowl to cool. Season very lightly with salt and pepper.
Peel shrimp, leaving tails on. Butterfly shrimp by making a deep slit down back of each from large end to tail, cutting to but not through inside
curve of shrimp. Devein shrimp, and place in a large bowl.
Prepare the Tacos: Pour oil into a large heavy-bottomed pot to a depth of about 2 inches and afix with a deep-fry thermometer; heat over medium-high
to 350°F. Combine flour, cornstarch, and salt in a medium bowl. Make a well in the center and whisk in egg until just combined.
Dredge half the shrimp in batter, shaking off excess. Carefully lower into hot oil and fry, turning occasionally, until golden and cooked through,
2 to 3 minutes. Transfer to a paper towel-lined plate to drain. Repeat with remaining shrimp.
Divide shrimp evenly among tortillas and top with slaw, hot sauce, and scallions. Serve with lime wedges.