Thank you. I will try your way.Even with original in spec receivers it can sometimes be tricky. There is a sweet spot where the top rail comes off or goes on just fine. I use a piece of round wooden dowel about 6 inches long to hold the tabs off the receiver. A piece a little thinner than a pencil will be gripped between the side of the top rail and the tabs without needing to be held. This makes it a lot easier to find the sweet spot without risking the tabs snapping down and marring the receiver finish as you wiggle the rail on or off. Hope that helps.