Is it possible to apply some kind of matte black finish over NP3 on the outside only of a slide? Perhaps Cerakote, or Duracote? Something which wouldn't require an application 'bath'? And if so, would it require any special prep? I'm considering buying a Glock from an associate, which has the barrel, slide, and internals coated in NP3. I like the idea of NP3's lubricity on the internal parts, but I'm not a fan of the two-tone look... Extreme longevity and corrosion resistance are not a concern; the NP3 provides plenty of protection, and I wouldn't mind if the black had to be touched up periodically, as long as it were not seriously chipping or flaking. Any info, advice, or experience with such would be appreciated!