For the salsa, in a medium bowl, combine the mangos, bell pepper, onion, jalapeo, cilantro and salt. Toss withthe olive oil and fresh lime juice. Adjust the seasonings as needed. Cover and let stand at room temperature for at least 30 minutes.
For the tacos, in a small bowl, combine the cumin, onion powder, garlic powder, salt and pepper. Rub the spice mixture onto the chicken thighs. Set them aside for at least 10 minutes to marinate.
Preheat a grill to medium direct heat. Grill the chicken for 6-8 minutes on each side, or until cooked through. Remove it from the grill, let it rest for 5 minutes and slice chicken into strips.
For each serving, divide chicken among 2 tortillas and top each with salsa.