You should have it Tennifer'd...
It already has been. Melonite and Tenifer are different trade names for more or less the same ferritic nitrocarburizing process. IIRC, "Melonite" is the trade name used by the America company...Burlington, I think? and "Tenifer" is the german company's trade name for it.
The black finish on the Glock isn't actually tenifer. It's parkerizing over a tenifer treated piece of metal. It's pretty neat, because you can wear a Glock slide through the park coating so that it looks like raw metal, but the tenifer is still there protecting it.