In a bowl, mix together the olive oil, garlic, Adobo, lemon juice, sazon, oregano and black pepper; set aside.
Using a small, sharp knife, make a cut on the side of the roast where the skin meets the flesh. Continue cutting, separating the skin from the flesh, leaving one end of the skin attached. Using the knife, make ½” deep incisions in the flesh, under the skin. Place the pork on a tray. Using your hands, rub spice mixture over flesh, pushing some of the mixture into the cuts. Place the skin on top of meat; wipe the skin clean. Rub skin with salt. Cover tray with plastic wrap; transfer to refrigerator to marinate at least 4 hours, or overnight.
Heat oven to 350°F. Transfer pork, skin side-up, to roasting pan; bring to room temperature, about 1 hour. Pat skin dry. Cover pan tightly with aluminum foil. Cook pork until meat is fork-tender and internal temperature registers 145°F, 3 - 3½ hours; discard foil. Increase oven to 450°F. Cook pork, uncovered, adding water in ¼ cup measures if pan becomes dry, until skin is brown and crisp, 20 - 35 minutes, checking pan every 10 minutes.
Transfer pork to cutting board; let rest 20 minutes. Remove skin and cut into pieces. Drain fat from drippings. Cut meat from bone. Serve with skin and pan juices.
After cutting the skin off the pork, if you find the skin isn’t as crispy as you’d like, simply transfer it to a foil-lined baking sheet, increase the oven temperature to broil, and cook, rotating the pan once, until crisp, about 10 minutes. Then, discard foil and oil.