Hmmm... I suppose it is possible that the 96-97's have a PCV, and the 98+ do not, as it may be a carry-over from Gen-1 or something similar to that as far as the years go. I can count on one hand the number of 96-97 cars I have come across over the years, and never did any engine work to any of them. But at the same time, I have bought plenty of Gen-2 engines over the yeas, some of which were 96-97's, and never noticed a PCV on them.
Possible they were removed on mine, or possible they were added on others? Mid-Year change?