Preheat oven to 325º
With sharp knife, puncture and score skin of ham.
Turn ham and score again to make grid-like pattern,
In small bowl, combine spice mixture, rub evenly over ham. Place ham fatty side up in large roasting pan.
Place 1 clove where lines intersect on ham, Rub sugar over ham pressing to pack.
Pour 2 cups of cola in bottom of pan and bake for 1 hour. In a container, combine whisky and remaining 2 cups of cola.
Baste the ham with the whisky and cola and continue to bake, basting every 15 minutes.until ham is cooked though
and meat thermometer reads 165º. About 2 - 2½ hours.
Remove and let rest 20 minutes before carving. Slice meat thinly across grain.