This task really took far too long to (almost) complete and I had to waive completion because of the need to get home for a nice Father's Day lunch at home with the kids. I assembled the parts -- the drilling through stainless steel was its usual pain in the neck self -- and riveted as necessary, creating a vent flap assembly and a vent assembly. The problem was the two brackets that go on the inside of the firewall. Basically, the Cherry rivets do not hold it tightly and one of the rivets goes through both the door assembly, the flap assembly, and the firewall into the bracket. So you have to rivet on the bottom part (that only goes through the firewall and then put the assembly on and try to hold the bracket in place to get the rivet through all the components.
This would be easier with a second person, of course. But I was fresh out of second people.
I got the passenger side on OK, but the one on the pilot's side was just flapping around and at one point, just came off. So now I have to drill out the SS rivet. Fun times.
Then I went home and had fun times.