There are some screw heads visible along each rail. In addition, the flipper buttons need to be unscrewed and taken out in order to remove the rail. These have hot glue keeping them in place. I was able to use a heat gun to get the glue nice and soft before pulling it off with needle nose pliers.

Once the rails are off, lay the EL mats on them to get an idea of the best placement. The clear portion will be punctured by the screws you removed earlier, so make sure it's lined up with the screw holes in the rail. I know some folks are running the wires through the mesh in the back of the cabinet, but I was able to route them around the back edge of the playfield glass.