1/2 teaspoon cayenne pepper 
1/4 teaspoon Cajun seasoning (your choice, but pick one without much salt) 
1 teaspoon seasoning salt 

Mix ingredients thoroughly. Set aside. 

One 5-pound Boston butt or shoulder cut 
Margarine 
Apple juice 

Score fat on roast but don't trim off. In a large enough container, soak meat in hot sauce (Tabasco). Move pork to a new, dry container. Massage the rub into every seam of meat and cut in the fat. The rub combines with hot sauce to form a thick paste. 

Wrap tightly in plastic. Refrigerate for at least 24 hours. 

Smoke pork roast 6 to 8 hours, depending upon the size. Baste with lots of margarine and apple juice. When meat reaches 140-150°F; remove and wrap in heavy tinfoil. Douse with a lot of bbq sauce. 

Put foil-wrapped pork back in smoker at 200-220°F. Cook three hours to 165°F.  When done, pull out the main bone. Pull the pork or slice it. Serve with additional bbq sauce.