In a large, resealable plastic bag combine the marinade ingredients, including 2 tablespoons oil, 1 teaspoon salt, and ½ teaspoon pepper. Place the chicken in the bag, press the air out of the bag, and seal tightly. Turn the bag to distribute the marinade, place in a bowl, and refrigerate for at least 4 hours or overnight, turning occasionally.
Soak the wood chips in water for at least 30 minutes.
Prepare the grill for direct and indirect cooking over medium heat (350° to 450°F).
Lightly brush the tomatoes with oil. Drain and add the wood chips directly to the lit charcoal or to the smoker box of a gas grill, following manufacturer’s instructions, and close the lid. When smoke appears, cook the tomatoes over indirect medium heat, with the lid closed, until browned in spots, about 8 minutes, and the bell peppers over direct medium heat until blackened and blistered all over, 12 to 15 minutes, turning occasionally. Remove from the grill as they are done. Maintain the grill’s temperature. Put the bell peppers in a bowl and cover with plastic wrap to trap the steam. Let stand for about 10 minutes. Remove the peppers from the bowl, peel away and discard the charred skin and stems, scrape away the veins and seeds, cut lengthwise into thin strips, and lightly season with salt and pepper. Set aside. Finely chop the tomatoes and place in a separate bowl.
To the bowl with the tomatoes, add the avocados, jalapeño, cilantro, lime juice, cumin, and ½ teaspoon salt and stir with a fork until evenly combined. Cover the surface with plastic wrap and chill until ready to use.
Remove the chicken from the bag and discard the marinade. Grill the chicken over direct medium heat, with the lid closed, until firm to the touch and no longer pink in the middle, 8 to 10 minutes, turning once. Divide the tortillas into two foil packets and warm over direct medium heat for 2 to 3 minutes, turning once or twice.
Cut the chicken into ¼-inch slices. Place the tortillas, chicken, peppers, and guacamole in separate serving dishes. Serve warm.