Here is our go-to on the BGE forum: (Credit Egret). I've never done it but everyone who has raved about it.
by John Hall (egret)
Maple-Bourbon Paste (recipe follows)
10-12 # cooked, ready to eat ham (bone-in Butt or Shank section)
1/2-1 cup Maple Syrup
Cherry and Apple Chunks
The day before smoking, place ham in a pan flat side down. Inject in multiple locations with maple syrup (use more than 1 cup if it will take it).
Smear the Maple-Bourbon Paste all over the exposed surfaces (except flat side). Cover loosely with plastic wrap and put in refrigerator until ready to smoke (You can remove ham from refrigerator up to one hour before cooking).
Stabilize egg at 250° with plate setter (legs up) regular grid with raised grid attached. Put 3 or 4 good size chunks of wood on coals, then place ham on raised grid. Cook until internal temperature reaches 140° (this should take about 5 hours).
2 Tbls. pure Maple Syrup
2 Tbls. freshly ground Black Pepper
2 Tbls. Dijon or Honey-Dijon Mustard
1 Tbls. Bourbon
1 Tbls. Vegetable Oil
1 Tbls. Paprika
1 Tbls. Onion Powder
2 tsp. coarse Salt, either kosher or sea salt