I see these roasting chickens on sale all the time at the Supermarket.
You take out the backbone, pat it dry, apply rub and cook it offset a lit chimney full of lit coals, place a piece of foil under the bird to catch chicken fat renderings, put the chicken down with the legs facing the coals and let it rip around 350 until the internal temp hits 145 in the breast, lightly mop it with BBQ sauce and then cover it back up til the breast hits 165, legs are around 180.
Here’s mine followed by some other BBQ guys I follow on YouTube
I put medium sized baked potatoes along side them as they take about the same exact time to finish if you poke em and partially soften them up in the microwave for 5 minutes before you toss them on the grill.
Perfect Baked potatoes on a Weber Kettle:
Prick them 3 or four times with a fork.
Place them in the microwave for 5 minutes.
Lightly coat with peanut oil and kosher salt on top.
Toss on the grill offset the coals for 45 minutes to an hour- 210F internal makes perfect mashed potatoes.
I guarantee success with this method.
Here’s Cooking With Ry-