I have used New England Chrome for small items, nuttin large like grills n stuff. Pleased w/their work but awfully expensive these days. Better get out your checkbook no matter where you have it done.
Superior Chrome here in San Jose, CA does awesome work. They are known here for working on classic car pieces including bumpers and grills. I had my rear tail panel stripped there.
I've got a customer that is restoring a late 50's Cameo. He sanded and buffed his pot metal and it turned out great. I'll have to ask him how he did it next Monday.