Quoted from johnwartjr:
Anything is worth doing with care, though, even if the originals are bent, I try to remove them carefully as you don't want to tear up the cabinet etc.
I showed a few pics and detailed the process here:
The nail may present an additional challenge, or it may not. On a couple cabs I've changed rails on, the nail pulled right out with a small pair of vice grips, without scratching the rail.
I removed some No Fear rails yesterday using mostly the same technique.
I use a knife like this one:
And I find it gets in close enough to the edge of the rail that it cuts through the tape nicely. No need to use the hammer or scraper at all Just get the blade up as high as you can and run it along the edge of the rail.
I had both rails off (without any damage to rail or machine) in 5 minutes. No heat, nothing.