To make the pickling vinaigrette:
Pour the canola oil into a large container that hold about 8 cups. Add the cider vinegar along with the capers, celery seed, kosher salt, Tabasco, dried onion, pickling spices, and the chopped celery. Whisk until well blended.
To cook the shrimp:
Pour the water into a large stockpot. Add the kosher salt along with the dried onions, lemon, celery, Worcestershire sauce, Tabasco, and crab and shrimp boil. Bring to a boil over medium heat, stirring to dissolve the kosher salt.
Toss in the shrimp, turn off the heat and cover the pan. Allow the shrimp to rest in the cooking liquid for 2 to 3 minutes, or until the shrimp are just cooked through. Take care not to overcook the shrimp.
Using a slotted spoon, transfer the cooked shrimp to the pickling vinaigrette, stirring to completely cover the shrimp.
Cover and refrigerate at least 24 hours, stirring occasionally. Serve the shrimp well chilled.
The shrimp will keep in your fridge for at least a week.