wash and dry them, and then rub them with either oil or butter, your choice, sprinkle with sea salt and place on one side of the grill. Make sure that this side has been heated and then turned off. The other side should be on high. The potatoes will bake with the indirect heat. About half way through baking I poke a few holes in the potato with a fork and turn it over. Let it continue baking until the sides are soft when squeezed or test with a fork.
or
wash and wipe dry potatoes. Cut slits into potatoes almost to the other side of the potatoes, being careful not to cut through the potatoes [potatoes must stay whole]. put pot in foil. Add butter knobs salt and pepper. Tightly wrap each potato. place onto higher rack on BBQ but over medium-hot coals for approximately 40 to 45 minutes, turning wrappings every 10 minutes. Prick with a fork through foil to check
few ideas here on recipies.........
http://www.barbecue-online.co.uk/bbq_recipes.htm