I'd have had several frames etc. PC'ed.
I assume you're having everything blasted before PC'ing.
Carefully remove the VIN plate. It won't survive, either the blast or the bake.
(Covered it might survive the blasting but the baking can damage it. There's stickum under the plate that will burn up.)
As far as the stamped VIN, unless the PC is really thick, the VIN is lightly stamped, or your DMV is really picky it shouldn't be a problem.
I've never had any trouble reading the stamped VIN on my bikes after having a frame coated.
The stamped VIN can be protected if you prefer during blasting to make sure they don't blast it away!
Remove the swing arm bushings, you should be replacing them anyway.
If you want to reuse the steering races I would remove them, they might fall out during the heat cycle.
(There's also usually grease inside the neck tube that's hard to remove if you leave the races in and can contaminate the PC during the bake.)
As far as threaded holes, any competent PC shop (one that knows how to PC bike frames) will have silicone plugs for all the threaded holes but never hurts to verify they understand what areas should not get PC'ed.
I only PC the large parts, frame, swing arm, stands. The rest I paint myself.
As far as finish, the PC'ers should have several choices, from high gloss to mat. I usually go with semi-gloss, close to the original paint.
Also, as Benelli states you'll have to remove some the coating at the ground points.
