Pit (underground) roasting a hog - any tips/tricks?

[DeadheadNM]

Looking to roast a dressed hog at the end of next month at a buddy's house as a sort of adios to the summer. I've attended mantanzas back in NM but only as a consumer. My step father has since passed but I remember him telling me they'd wrap the pig in burlap and pillow cases before burying it in the pit. I'm trying to dial in some greater detail. Have the pig lined up for a Sept 20 butcher date from a local farm: https://www.deutschfamilyfarm.com/

Any helpful tips/tricks?