Upper intake (Plenum) question 97 88 LS

I got the old plastic upper intake (plenum) off my 1997 Olds eight eight. When I took it off the gasket and everything came off. No real problem but leaves me with a question. As most know the gasket is a thick plastic gasket that has a bead on each side. Going from front to back there are two plastic supports that hold a pipe. I am guessing one end is open to the cavity and the other end goes into the hole going to the PCV is this correct? I looked in my manual and did a search online but could not find anything that confirms this. Too muck to have to take the new one off later so please advise me.
Thanks!

Correct, while you are in there, remove the 2 inside corner lower int. bolts ans seal them with rtv, oil can migrate up these bolts.