I trim the fat cap down to about 1/4" I carve out that big chunk of fat next to the point.
I do fat side down because I like the bark on the top side to be nice and crispy. I do spritz with a mix of beef broth with worcestershire and rub. Same thing I inject with. Layer on that flavor then let it dry out and condense on there.
After about 4-6 hours at (250 -275) it reaches 165 and stalls for about 20 minutes, I wrap in butcher paper. Butcher paper keeps the bark from getting mushy like it tends to do in foil. Then in the oven it goes with temp probes in the flat and point so I don't have to watch an outside fire.
275 oven temp or 300 if I'm in a hurry. Once the temp probes reach 200 I start use my third thermometer to poke it and see if it is tender. Usually have to cook a little more until it reaches 205. point is usually following the flat by about 10 degrees. if its that far I'll drop the oven to 220 and let it set before pulling it. give the point more time to catch up without overcooking the flat.
Let it rest in the wrap until it cools to about 130. Then start carving across the grain.
I did learn a trick to cut some score marks across the grain at the flat and the point, before you start smoking, so you can easily see how to cut after its cooked and the bark is hiding the grain.
These little flaps hold more rub and bark which I save for me.