Sometime ago I had everything on the 69 blasted, powder coated first with a rust protective coating and then done in semi flat black. I recall it being less than 2000 at an industrial coating factory just a block up the street form Corvette Mike. And by everything I mean everything from the frame to the hinges to the braces under the dash. All the suspension, all the under dash brackets, anything that was steel and looked even a bit dirty, went to the coaters. Told him put it in line when it gives me the beast price.
This approached worked out great - he blasted everything and refinished it all in much less time that if I had wire bushed, dipped it in degreaser, and then took spray paint to it. Allowed more time for other parts of the car. Everything came back wrapped in paper and protected. I was like a kid at Christmas unwrapping for a week.
There is also a fantastic metal polisher & chrome shop in Santa Ana. Sihilling. Actually, he does not do the plating but he does all the prep and polishing. That is the real work anyway, not dipping a bumper in a vat of chemicals. His number 714 543 7051. Charles is his name or the manager, Lorina.
Good Luck, George