In a large bowl, whisk the lime juice, 1 teaspoon salt and ¼ teaspoon pepper. Mix in the cabbage, onion and half the chili. Set aside, tossing occasionally, while you prepare the shrimp. In a medium bowl, stir together 2 teaspoons oil, half the garlic, the chili powder, 1 teaspoon salt and ½ teaspoon pepper, then stir in the shrimp.

In a 12-inch nonstick skillet over medium-high, heat 1 teaspoon of the remaining oil until shimmering. Add half the shrimp in an even layer and cook, undisturbed, until deep golden brown on the bottoms, about 2 minutes. Stir, then transfer to a plate. Repeat with another 1 teaspoon oil and the remaining shrimp, but leave the shrimp in the pan. Return the first batch to the pan. Add the remaining garlic and remaining chili; cook over medium, stirring, until the shrimp are opaque throughout, about 1 minute. Transfer to a clean plate or a bowl.

Add the remaining 1 tablespoon oil and the cilantro to the cabbage mixture; toss. Taste and season with salt and pepper. Divide the shrimp among the tortillas, then top with the cabbage mixture. Serve with lime wedges.