I use F 409 and paper towels to get it pretty clean, then a "Glass Plus" wipe over the whole plane to finish up and shine it up. The GP wipes are awesome but too expensive to use for the initial oil removal, IMO. Also something new since I stopped flying 20 years ago, little exhaust extensions you stick on the muffler to deflect more exhaust away. Really reduces the oil/etc on the airplane if you aim it right.

-Greg