I came to this forum to inquire about finishing the plate chokes, so I'll just add my comments/inquiry here...
I am finally getting around to building my S3X. I've been very much wanting to get it glowing, but haven't been able to until now.
Fully unpacking the kit bits, I had planned and prepared to also apply some finish - a hammered finish - to the mounting bits of the chokes, like the power transformer bell/cover, for cosmetics and to protect from rusting. I see the plate chokes are now nicely finished with bells, and all the metal parts are covered with a finish. This is all good. It looks like now I don't have to worry about finishing these to protect anything from rust.
I'll leave the chokes as is and just paint the bell.