In a blender, combine chipotle pepper, orange juice, lime juice, oil, soy sauce, cilantro, honey and chili powder to make marinade.
Place steak in a rimmed baking dish and pour marinade over. Cover and refrigerate for at least 3 hours or overnight.
Preheat a charcoal or gas grill to medium-high. Remove the steak from the marinade, season with salt and grill for 4 minutes a side.
Transfer to a cutting board and rest for 5 to 10 minutes.
Combine all ingredients in a bowl and stir. Refrigerate until ready to serve.
Place tortillas on a baking sheet and toast both sides under broiler until lightly golden. Slice steak into thin strips. Serve on tortillas with mango salsa.
Nutritional analysis per serving (2 tacos): Calories 646; Protein 38 g; Carbohydrates 54 g; Fat 32 g; 44% Calories from Fat; Cholesterol 98 mg; Sodium 1199 mg; Potassium 797 mg; Fiber 4 g