Just used 0.3 lapping film for the first time, on a test Frontier. The difference is astounding after smoothing between the tines, it writes like my old 45 used to. It's so smooth, there's next to no feedback at all, so I might get a sheet of 1 micron stuff too.

As it's backed with an adhesive, I'm thinking of making up a wee tool by wrapping a short band round a 616 barrel, to smooth out the inner cap of a GF P51 cap where it's been causing hood scratches. Any nays before I give that a go?