For the roasts: Pierce the rib roasts with a knife to create small holes. Stuff the holes with the garlic spears and jalapenos. Transfer the roasts to a large tub or ice chest.
Pour the cooled marinade into the ice chest, followed by the ketchup, pickle juice, Worcestershire sauce, spicy brown mustard, black pepper, salt, lemons, beer, limes, yellow onions, chopped garlic and ginger. Allow the roasts to marinate for at least 5 hours or up to overnight. (If marinating for more than 6 hours, ice should be added after the 6th hour.)
Remove the rib roasts from the ice chest and pat dry. Apply the spice rub generously all over the roasts.
In a starter barrel or chimney, light natural wood charcoal. Allow to burn down to embers, about 15 minutes.
Place the embers in a smoker and top with a small handful of soaked mesquite chips. Heat the smoker to 200 to 225 degrees F. Every 20 to 30 minutes check the charcoal and wood to see if more need to be added.
Smoke the roasts until the internal temperature reads 140 degrees F, 6 to 8 hours. Turn and reposition the roasts every hour to ensure even cooking.
Let the roasts rest for 5 to 10 minutes. Cut the ribs off and set aside. Cut the roasts into 3/4-inch steaks. Serve.