Herein lies clearance issues that could bugger things up on a potentially tight squeeze. My .2c from working on restoring old cars and guns (this is the first thing I've put together in the past year younger than '67), is to assume that when putting something together from reproduction parts of various vendors to NOT PAINT OR MODIFY ANYTHING UNTIL YOU HAVE EVERYTHING. The difference in times between pcbs, then plates, then cases means that you're basically hoping that everyone communicated perfectly in the first place, but you may have to make modifications just to get things to work and fit, not to mind aesthetics.
This part of the project is not so much electronics stuff, as it is metal assembly and prep. Tolerances may differ, lines of communication will be crossed. Let's first get some rough stuff in our hands and see what tweaks have to be made first. But I can tell you now you cannot get a shop selectively powdercoat something on one side at a reasonable cost. They suspend the object, throw a charge on it, then spray oppositely charged particles at it and bake it to create hopefully a solid finish. I know of places that can do two tone (not bare and coated), but they do that using really expensive masking materials. Again, assume anodized aluminum and bare SS are your choices folks, unless we have some mad scientists at home who aren't afraid to wreck a few plates in their ovens.