Using long knife, make lengthwise slit in center of thickest end of roast to form deep pocket, about 3” long. Pierce beef all over with tip of knife. Transfer beef to large zip-top bag (or to non-reactive container with lid). Pour Mojo over beef; seal bag. Refrigerate at least 4 hours, or up to 24 hours for best results.
Heat oven to 275°F. Remove beef from refrigerator at least 30 minutes before cooking; discard marinade. Using paper towels, pat beef dry. Stuff pocket of beef with chorizo. Using kitchen twine, firmly tie beef in 1½ ” intervals, perpendicular to pocket, to enclose chorizo. Sprinkle beef all over with Adobo.
Heat oil in large Dutch oven, or large oven-proof pot over medium-high heat. Add beef. Cook, flipping beef with tongs, until golden brown all over, 5-7minutes; transfer to plate. Add onions to pot; cook, stirring occasionally, until soft, about 3 minutes more. Pour wine and 4 cups water into pot. Bring liquid to boil, scraping up browned bits from bottom of pot with wooden spoon. Add carrots, olives, bay leaves, oregano and beef to pot. Tightly cover pot; transfer to oven.
Cook, flipping roast every hour, until beef is fork-tender, about 4 hours, adding potatoes after 3 ½ hours.
Transfer beef, potatoes, carrots and olives to platter; tightly cover with foil to keep warm. Place pot on stove over medium-high heat. Bring liquid to boil. Cook, stirring occasionally, until sauce reduces to 2 cups, about 5 minutes. To serve, cut beef roast into ½” slices. Pour sauce over beef. Serve warm.