I use Adams compound and polish to get mine to come back to life. It's a little pricey, but I have had great results with it. It was recommended to me by a friend 15 years ago, and I have used it since.
https://adamspolishes.com/collectio...products/adam-s-complete-5-5-pad-polish-combo
I started by using a clay bar on the entire body with Mothers spray polish from the local auto store. I sprayed a small area of a panel and the clay itself, and then work the clay in a uniform direction until it removes the heavy oxidation and wear. You'll feel the difference after doing 1 or 2 spots. After each area, just work the clay like putty to clear it up and prep it for the next area.
Once I had the entire body clayed, I moved on to the correcting compound and the polish from Adams with a variable speed electric polisher that I picked up from either Harbor Freight or Sears. I always spray the body and the pad with a spray polish as I move to each new area.
You'll want to be careful and really pay attention as you go to see how much the correcting compound is cutting into the paint. Mine was dragged behind a RV most of it's life and probably only washed once a year. In some areas it didn't take very much effort/time/cutting to go from heavy oxidation to patina.