I know the plenum hoses were stapled to the plastic defroster outlets at the dash. I see that eveidence (of the staples) in the original ducts. However, I don't see evidence of staple holes in the plenum. Were the hoses just slid onto the plenum? Or were clamps used at the plenum? Or were they also stapled at the plenum and either I cannot see the old staple holes or perhaps the guy working on my car that day just didn't install the staples?