Anyone used a saddle mount on an 870 to mount optics? I have a Remington 870 Super Mag turkey model. It came pretapped for a base, however the holes were not tapped straight down the receiver. Obviously a factory flaw. Due to this, you cannot mount a standard picatinny rail on the receiver, because it will not sit straight and fit flush down on the receiver. I don't feel comfortable tapping more holes into the receiver, as I fear that will weaken the integrity of the receiver, causing cracks from the heavy recoil of 3.5 magnum shells. So it seems I am stuck with the saddle mount option. Has anyone used one? Curious if they are a solid mount that will not move around on me or rattle loose with repeated recoil. Thanks for any help