Not content with GM's frankly woeful parts bin attempt at a solution for '77-'82 cars as per below, I decided to make my own.
The later console has volume and tone knob pedestals which raise above the surrounding area at the bottom by about 3/16" which requires the cover plate to have this as a recess and to be at least that tall to accommodate this feature - nothing can be done to avoid this.
Here is my first prototype with peg holes to confirm location and check rear recess depth suitability etc. I also used this prototype to test various surface finishes from 600 grit all the way to polished to assess which finish best reflects the satin finish on the native plastic.
The filament used is ABS to replicate that used on the rest of the interior plastics.
First prototype after some surface finish testing....
This at least confirms it fits, looks good and that I can chose what finish I want from rough all the way to mirror polish.
With the control knob pedestals requiring a certain thickness of cover plate to house them, I decided to replicate the perceived thickness of the segmented panels within the later consoles, including their tapered edges, as well as including the chrome detail, however I decided rather than continue to build further depth extension, I'd recess the chrome detail into a channel of the same width as the rest of the chrome ridges on the interior. I also added a boss on the rear which i can attached threaded rod to, enabling me to affix the plate through the regular radio knob spindle holes in the console.
Second prototype ready for refinement and finishing...
Bevels, angles and depth to match existing console panel design...
Mounting rod bosses...
This is fresh off the table and needs significant refinement and finishing, but shows what I'm trying to achieve - something that looks like GM actually tried.
