I definitely like the cabinet scraper idea. Not too much money for what looks like a very useful tool.
I used that technique to burnish the fretboard edges on my '02 SG Special Faded. But, it created a slight scalloping effect between the frets. I had to follow up by sanding down the fret ends including the tangs, and then polishing the fret ends again. It turned out OK, but still nothing like a the rolled fretboard edges that came with my Fender, G&L, and Music Man guitars. I wish I could see how those manufacturers do their rolling, at the factory.