Rub 1 tablespoon lemon-pepper seasoning into roast, place roast in a large container.
Pour marinade over roast, and cover.
Refrigerate 6 hours, turning roast occasionally.
Remove roast from marinade, reserving 2 cups marinade for use in Savory Barbecue Sauce.
Rub remaining 1 tablespoon lemon-pepper seasoning into roast.
Soak mesquite or oak chips in water 1 to 2 hours.
Prepare fire in grill; let burn until coals are white.
Rake coals to one end of grill; place wood chips over hot coals.
Place roast at opposite end; cover with lid, and cook over indirect heat 2 1/2 to 3 hours (approximately 22 minutes per pound).
Cook roast until the thermometer registers 140° to 170° or to desired degree of doneness, basting at 1-hour intervals with Savory Barbecue Sauce.
Sprinkle roast with lemon-pepper seasoning before slicing.