In a large mortar and pestle, add in salt and garlic. Crush until garlic becomes a paste. Place garlic into a small bowl and add remaining ingredients except for pork. Set aside.
Dry pork and score skin with a knife. With a sharp knife, lift up skin and poke holes one inch deep all around pork.
Wet pork with vinegar and let it sit for ten minutes.
Drain excess vinegar and season pork with garlic mixture.
Loosely cover pork in a large bowl and refrigerate 12-24 hours.
Preheat oven to 300 degrees Fahrenheit and cook pernil for six hours, loosely covered.
Raise heat to 375 degrees and cook for an hour, uncovered.
Shred pork and place into a slow cooker or pan and keep warm until it's time to serve.
Notes
Use a food processor to pulse the garlic a few times if you do not have a mortar and pestle.
Leftover pernil can be refrigerated up to 3 days and reheated in the microwave.