Ive not done it either but I have watched many many shoes on it.
How depends on your set up. Seen a lot done with a stacked cinder block approach with expanded metal over the top and pieces of roof tin to cover.
Same concept in the ground.
Either way, I’d start a feeder fire and shovel coals under it to keep the temp in the
Low and slow. 250-280.
Skin side down. Use a saws all to cut the ribs at the spine to get it splayed out flat. Take some ground pork and pack over the tenderloin to keep it cooler and slow the cooking.
Rub the inside heavily with the dry rub of your choice.
Expect it to take 12-18 hours
Let us know how it goes...
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