I'm back, after about 5 hours of work! The good news is that the car looks LOTS better than before. The
single stage red paint was pretty oxidized and has all sorts of contaminants in it. I went with mostly Meguiars products as they were handy - I discovered I'm out of a lot of my Zymol stuff - except for using 3M Imperial Hand Glaze. This means I washed the car thoroughly with their soap, Quick Detailer with clay, Paint Cleaner, Polish, 3M Glaze, then Gold Class wax.
By the time I finished, it was too dark to take an after photo, so I'lll add one tomorrow, but the car came back to it's original Guards Red and has a deep mellow glow to it. Not as nice as the gleam I get from my other 2 Porsches, but those have clear coats; at least now you can tell they're all the same shade of red.
The bad news: going over the paint in such detail makes it clear I'll need to repaint the car next spring: some previous paint repairs are slightly off and my mirrors and rear bumper are slightly different shades of red than the rest of the car, and there are some water spots that seem deep in the paint on the hood and next to the rear hatch.
For now though, it's acceptable. Thanks to everyone for their help and advice in this and the other thread.