Place crab in a bowl and run fingers through it to check for pieces of shell. Break up crab a bit with finger tips but leave several large pieces. Add chili sauce, lemon zest and juice, parsley, hot sauce and Worcestershire to the bowl and toss to combine.
In a food processor, process the chopped veggies into small bits by hitting pulse several times. Line a plate with a few sheets of paper towel. Scrape veggies onto towel to remove liquids. Transfer chopped celery, pepper, garlic and onions to the crab. Stir to combine veggies and season the salad with coarse salt and pepper to taste. Place crab salad in a serving bowl and top with crackers. Surround the salad with lettuce "cups". Spoon the salad into the crunchy pieces of iceberg as you eat.