To make the pork:
Place pork in slow cooker.
In bowl, whisk together marinade ingredients. Pour over pork.
Cook on low for 8 hours or high 3-4 hours, until pork shreds easily.
To make the veggies:
Combine vinegar, sugar, and salt, whisking until sugar is dissolved.
Add veggies and toss to combine.
Let sit for at least 30 minutes.
To make the sandwiches:
Shred the pork with two forks, keeping it in the liquid from the slow cooker.
Spread desired amount of mayo on each roll.
Top with pork, pickled veggies, and cilantro.