Prepare the marinade for the pork by combining the sour orange juice, oregano, chopped garlic, and oil, to taste. Let marinade stand for 1 hour.
With a very sharp knife, cut ham across lengthwise, exposing the bone. Cut around the bone around to remove it.
Use small cuts to butterfly the ham, so it lies flat.
Trim into a rectangular shape. Discard any excessive fat. Season the meat with marinade and set aside, refrigerated, for at least 2 hours.
While the pork marinates, make the rice and beans
Bring beans, 5 cups water, bay leaf, and 1/2 red bell pepper to a full boil. Simmer until beans are soft. Strain and remove the pepper. Reserve the water (if necessary, add water to make 4 cups).
Sauté the diced pepper, onion, chopped garlic, and oregano in 2 tablespoons olive oil until translucent.
Add the rice, beans, and water and bring to a boil. Season with salt. Reduce heat and cook covered until rice is soft
Sauté crushed garlic cloves in the remaining 1/4 cup olive oil until brown. Add crushed garlic to the rice. Season with vinegar and let stand until cool.
Place rice stuffing in the middle of ham and fold both ways until stuffing is fully covered. Tie with string both lengthwise and across
Put in slow cooker and cook on low for 8 to 10 hours. Leave meat in the slow cooker on the “warm” setting for about 4 more hours or until the meat will easily pull with two forks and the internal temperature reached 150F.