I'm no pro... just a guy in his garage. Never messed with a drip rail before and never done body work at all prior to this car, so take it for what it's worth (not much).
A good place to start with drip rail removal is with a decent drip rail.
After you find a decent drip rail, you'll need a good way to destroy them.
I prefer the grip and bend the hell out of it method.
After it's all bent, its time to chop. I took a page from someone else's book and did the chop/tack weld method. (6 inches at a time)
After the whole thing had been chopped off and tacked, I welded between the tacks and cleaned it up with a flap wheel.