Place slices in a large non-reactive bowl. Combine two tablespoons of salt and the water. Stir until salt is dissolved. Pour salt water over cucumber slices. Cover and let 2-3 hours. Drain the cucumbers and discard the salt water.
In a nonreactive pot, combine vinegars, water, sugar, and salt. Cover, bring to a simmer until the salt and sugar is dissolved. Remove from heat and set aside.
In the bottom of a pint mason jar, add 1 teaspoon of dill seed, 1/2 teaspoon pickling spices, and 1 teaspoon minced garlic and 1 teaspoon minced onion. Fill jars with cucumber slices.
Using a funnel, carefully pour vinegar mixture over the cucumber slices, leaving 1/2-inch of room between the pickles and to top of the jar. Wipe rims with a clean damp rag or paper towel. Place a lid on each jar and secure tightly.
Allow jars to set for 3 weeks before opening.
Jars will last for up to three months in the refrigerator. Pickles can also be preserved using the water bath canning method. Properly canned pickles should be store in a cool dry place and are good for up to one year.