Place carrots, daikon and salt in a colander over the sink and mix together. Allow to sit for an hour, tossing together every 15 minutes. Thoroughly rinse and place into a mixing bowl.
Place sugar, vinegar and water in a small pot and bring to a simmer until sugar dissolves. Allow to cool for 10 minutes.
Pour sugar mixture over carrot and daikon and place in the refrigerator for an hour.
Place marinade ingredients into a mixing bowl and whisk together. Add pork belly and toss together until well marinated. Place in the refrigerator and allow to sit for 30 minutes.
Place 2 tablespoons extra virgin olive oil into a grill pan and heat over medium-high heat. Sear and cook pork belly on each side for 4 to 5 minutes. Remove from heat and set aside.
Place mayonnaise, green onions and garlic into a small bowl and stir together.
To assemble: Spread a small amount of the spread onto the tops and bottoms of each bun. Place a couple pieces of pork belly into each bottom bun and top with cucumber slices followed by a small amount of daikon and carrots. Place tops on each slider and gently press. Serve.