Very easy to do. It's installed the same way the stock one was. Remove the top screw in the rear above the handle, press the switch and slide off the handle, slide the new tube on with the sling swivel mount attached to the front, insert the stop washer with the long screw and tighten. The switch is very tough to press in but theres a trick to doing it. When you press it to adjust the rear handle, don't use the lower tab but press the base right above the tab.
