HDBR builder, I'm not trying to be difficult with my response, but my point is I simply want paint/varnish suggestions for the motor board, base, and back that is being used today in models such as the Cornwall III, Heresy IIi, Forte III. They all look similar, to my eye, from pictures on the site.
I'm not changing components, I'm not moving the woofer up, I'm not moving components to front mounting, I'm not adding a terminal cup.
I have a standard Cornwall I from 1984, CBR. B-3 network. Serial 8404603. They were varnished, I believe, after they left the factory.