Yep, it's the entire shoulder, Butt and Picnic together.
What a great cut, and seldom seen in today's grocers or even butchers.
I'm going to say, " Cook it Whole!",
just to have the experience.
You can always vacuum bag the leftovers into individual meals.
Go ahead and inject it thoroughly, and then crosshatch score, and get the rub in good.
Smoke it Hot-n-Fast at 275°-300°.
That's a lot of meat and more importantly, bone, to bring up to temp, tender and ready for pulling.
And by all means, make a good finishing sauce to go with it.
SoFlaquers is a good one.
And it really helps keep reheated PP moist.