When I pulled apart the front suspension on my 50 year old TR3 during the restoration, 90% of the original PAINT on the springs was still there after I cleaned off all of the dirt and grime. A few rust spots, but not alot. I gave them another coat of PAINT! It worked for 50 years, so that's good enough for me. BTW, when I scrubbed the chassis down, most of the original paint was on that also. The body was a rust bucket however. So bad, that I just went and got a different body for the car. Maybe the engine chassis oiling system had something to do with keeping the paint on those parts. :laugh:
Personnally, I think too much money is spent on powder coating stuff when a rattle can of Rust-O-Leum would work just about as well for most applications.