In Australia we use a product called Innox. It is similar to WD40 but with more lanoline, which is sprayed/wiped on the chassis after rubbing the tubing to a light grey color with very fine grit paper and/or scotch bright pads. The result is great! But it is a tiresome process. Best idea is to get any little kids that like hanging around to do the job. They tend to be wildly enthusiastic about working on a real race car, and their little fingers can get into all the tight corners.
The Innox seems to last a couple of weeks until finger and hand prints start to show up again where crew have been handling the car. I can't believe how much acid must be in the human skin to get through the Innox. And, the more progress you make on the chassis, the more difficult the job becomes due to the profusion of brackets and tabs to be negotiated. However, you'll find the term "labor of love" must have been coined for this work.
Good luck, and enjoy caressing your tubing.
Cheers
Von Zoom
