Well, a 15 minute project turned into a hour and a half project. I purchased a Desing Machine low mount for the MRO and installed it pretty easily. However, removing the top rail that came on my rifle was a bear. The front screw came out fairly easily. However the rear one stripped as soon as I applied pressure to break it loose. Not sure what torque spec they used, but somebody at FN needs to lay off the caffeine (probably Jonas) and check their wrench. I ended up having to drill the head to get it out. However, it was worth it. I love the mount and side rails, as well as the MRO. Now i just have to wait for the BATFE to approve my stamp. They did already cash my check, so hopefully soon.