Well, I did mark everything and put it back as it was. However, I did not check function before disassembly because the control head was out and had not been replaced. I installed the new one during reassembly. Fan didn't kick on very strong either, I have to diagnose that still. Hot cold slider works great and I can hear the door reposition. The vacuum actuated door shown moves full swing in only one direction, inward.
I tried to justify it as moving some air to the side vents but it would just come out the center also...
Box had been out before for sure. Two of three studs were bent and one was missing the nut. I really took time doing it to make sure it was right, but the gap between disassembly and add on parts arrival was probably a factor too. Plus AC needs charged and core isn't plumbed yet. I just wanted to do it before carpet and seat go back in so it was easier.