Chrome plating is much harder than steel. That's one of the main reasons truckers dip 90% of their big-rigs in the stuff! 0000 won't scratch it unless you REALLY scrub the plunk out of it. By the time it would start working into scratches, you will have had the rust problem solved 4 hours ago. ;)
Or you can use NevrDull, which is basically steel wool, cotton, and a chrome polish/treatment.
Work smarter not harder, through metallurgy! :)
- CK