Combine all of the sauce ingredients in a bowl and mix well. Adjust the salt to taste. Cover with plastic wrap and refrigerate until ready to use.
Rinse the fish under cold running water and pat dry with paper towels. Cut the fish into 1 inch cubes and put in a large bowl. Add the Worcestershire sauce, garlic, salt and pepper and turn the fish carefully to coat. Cover with plastic wrap and refrigerate at least 20 minutes or up to 4 hours.
Put the flour on a plaate and toss the fish pieces in it a few at a time, until they are all evenly coated.
Heat the vegetable oil in a large pot over medium-high heat to 375 degrees F. Carefully add a few pieces of the fish at a time, shaking off any excess flour before placing them into the oil. Fry until the fish pieces are golden brown all over, about 4-6 minutes. Then transfer them to a paper towel lined plate to drain.
Meanwhile, heat a medium skillet over medium-high heat. Add a tortilla and warm for 10-15 seconds. Flip the tortilla and warm until it is pliant and heated through, another 10-20 seconds. Place on a plate and cover with a towel to keep them warm. Repeat with the remaining tortillas.
Spread a dollop of the chipotle tartar sauce onto a warmed tortilla. Add a few strips of cucumber and top with 3 or 4 pieces of fish. Cover with a few arugula leaves and cilantro leaves and a sprinkling of the orange zest. Serve with more chipotle tartar sauce and the lime wedges on the side. Enjoy!