The pavilion seats are pretty good. I've sat up there, but not in the coke section. It seems weird to be up so high, but you've got a nice view and you'll enjoy it I'm sure.
The coke section is alcohol-free though I believe. No beer or liquor allowed. Correct me if I'm wrong someone

As for getting to that section, you
do have to go inside the park just like you would for any other section. I forget which gate, but enter on the Green Monster side and you'll see signs in there for directions to the pavilion. There's probably a couple different ways to get up there, but I do remember seeing a stairway over by the Gulf sign next to the Monster.