Plenty more progress today! Here's where we were when I got home from work:
First, I re-installed the plastic box on the center console tunnel. I then put the HVAC unit, the stereo, and the DIC back in the dash tower. Then finally installed some carpet!
Then I attacked the trim piece that goes along the transmission tunnel. This contains an exposed plastic piece, which I painted, with carpet glued on the rest of it. Here is what it looked like with the old carpet peeled off:
I used a strong spray adhesive on both the plastic and the back of the carpet, and glued the new black piece on. I was then able to muscle it into the car. I also re-installed the seat belt unit along the tunnel.
The black carpet is going to look amazing when it's done.