Jeff W's nice new MIM Strat has several areas of low frets that require leveling to remove string buzzing and allow for better overall playability. I removed the strings, leveled the fingerboard (via the truss rod), taped off the headstock nut area and upper body area, colored the fret tops with a Sharpie pen, and began leveling the frets with a special fret level file.
After three careful file levels (recoloring the fret tops before each attempt), the fret tops are smoothed out with 100, 150, 320 and 600 grit production paper wrapped around the fret leveling file ... then the flattened fret tops are recolored and ...
... crowned with a special concave diamond fret crowning file that allows passes of both 150 and 300 grits. Most of the Sharpie coloring is removed from the fret sides, leaving a very thin 1/32" (or so) colored line on the very top of each fret.
A block of neoprene rubber has one rounded edge wrapped in MicroMesh cloth, from 1500 through 12000 grits, to round the very fret top crowns and polish them uniformly smooth.
All done. Next, I'll clean the fingerboard and frets with naphtha (lighter fluid), thoroughly dry off the board, wipe the board down with my own lemon oil formula and allow it to soak in for about a half hour, then wipe off the residue and buff with a dry, stiff paper towel. After that goodness, we're ready to string up and begin the guitar's final setup.