In a medium size saucepan - add about 6 cups of water, add some salt and bring to a boil.
Add pasta and cook until almost done, stop cooking slightly before al dente. You don't want to overcook the pasta because it will continue to get softer and absorb liquid from the sauce. When pasta is done, rinse in cold water until it is completely cooled.
While the pasta is cooking, mix up the sauce. Add mayo, Italian dressing, pickle juice, mustard and seasoning to a small bowl and mix well.
In a large bowl - add the pasta, frozen peas, cheese and crab chunks (optional). Pour the sauce over the top and mix well. For best results, refrigerate for 2 hours to let the flavors meld together and the pasta to chill. Enjoy!