I just did one if these last weekend! It turned out sooooo good.
I took a very simple approach... I rubbed it with some Rib Rub, got a really good coating on it, nice and thick.
Depending on what temp you want to bring it too.. I did Medium.
You can't go wrong with a roast.... just don't overcook it!
While you are at it, make a Fattie, or some ABT's too, it won't take up your whole grill..... so smoke lots of stuff with it!