I spent some time under the Impala today afterall. I painted part of the passenger-side frame rail so that I could install the exhaust back on without having to worry about getting black paint on it. I also installed the rear-most portion of exhaust piping. All I have left to do with the exhaust is hang the crossover pipe and muffler. I should be able to get that done in half a day or less.
The next Impala project will be to replace the old distributor points system with modern electronics. That'll involve removing the distributor and replacing internal distributor parts. There will, I'm sure, be lots of pictures. It seems that the more difficult-looking a project is, the more pictures get taken. That helps when re-assembling stuff.