My brother an I will be doing a hog this coming Saturday 40-50lb range. We've done this 3 times before, and he's done several pigs and a few lambs on his own. We'll be butterflying the pig and cooking it on what's basically a catering style grill. Shallow fire tray with adjustable grill height and a massive barrel style cover, with an off set fire and some water pans it does pretty well for this sort of thing.
We've got a nice handle on how we're going about it. ~225F, skin down protected by foil initially, basting with apple juice/vinger and lard on the meat side. Depending when we pick up the hog we'll either inject or let it take a long sit with a heavy rub. No sugar outside the juice. Expecting 6-8 hours not including rest but planning for longer. Maintaining a consistent temp can be tough in this grill. Using charcoal and a bit of hardwood for smoke.
Anyone have additional tips or advice?