Bubba chopped up my defroster vent so as to hook up a flex hose for the VA system. Ok no problem I’ll just get another duct, right? This duct is held on by some type of screw visible through the windshield. (nice design) I don’t see how I can loosen these screws with the windshield in place. Anybody done it? And I’m sure that hardware store screw ain’t right. Can someone post photos of an original so I can see what type of screw used in 1970?