Bought more rusty cars in the last 2 years then in the last 20. Lot more imports into AZ to make up for the bunch that's already left I guess. Anyway's what's the trick on making things like rearends, control arms and maybe gas tanks, that have a little bit of surface rust, look newer/factory without just painting them? Have one car right now where everything looks great, except the diff. Thanks for any input.