Update Jan 7, 2018...
0. Silver polish (I used goddards silver cleaning foam) does work much better than mechanical polishing to remove the tarnish. Now all grid crevices are tarnish free and an even silver color.
1. The clip CAN be easily removed. Just unscrew the cap on the top (will take some delicate silicone/high friction rubber gloves to get a grip). this lets you separate those parts and do any maintenance on the cap just by itself without the assembled parts getting in the way. This will also let me undo my very big mistake of stripping the gold plating off the clip.
2. when you unscrew the cap and clip, the internal snap-in parts will come out, which is helpful for cleaning and maintenance
3. The nib assembly and feeder tube (breather tube?) come straight out of the gripping section, no screw action. Took some rubber gloves to get enough friction on the portion of the nib I could grip. Helpful for cleaning, but probably something to avoid too much of.
Next steps for me:
1. Refinish (very lightly) the tarnish free grid surfaces
2. Replate the clip and cap in 24k gold
3. Cast the gripping section in silver and gold plate (just for kicks, we'll see if it works)