Having powder coated all my rails, they're very easy to remove. It takes me about 2 minutes to get a side rail off. The rail is garbage after. The rail is held on by the front bolt, sometimes a back screw or nail, and double sided tape.
1) remove the front screw
2) fold down the back board and remove the back screw or nail of it exists
3) get a long flat blade screw driver and start at the front.
4) Jam the screw driver in under the rail ripping the tape. Gently and slowly pry outward. You should never hear splintering wood. If you do, stop and go slower. Jam the screw driver in and pry gently letting the tape separate from the rail or the cabinet on each place you jam. You should jam it in every two inches or so and should not have to pry very hard
The rail will come off all bent leaving some tape on the cabinet. This tape can help you secure the new rail on. You definitely do not need so much tape as they uses before. Pinballlife sells new rails and tape. I put about 5 2" strips of tape on the new rail and stick it on with the screw in front and one in back that has a shallow enough head to clear the bracket when the cabinet folds down.
It's actually a much scarier sounding task than it is.