What he said. A heat gun or hairdryer should work too. I'm still surprised your motorcraft PCV didn't come with a new one though. I'd ask the parts dude if it's supposed to or not. I know mine did and I just got it last weekend.
I got one about a month ago that didn't come with one. The next day I called to get the boot and they have completely redesigned the setup. There is no longer a plastic boot, it goes to a rubber elbow. Now for the good part...the only way to get this elbow is to get the entire hard line from it to the IAC. It is formed slightly different and comes with protective foam around it to keep it from rubbing on all the other crap around it.