I currently have the smooth free float forearm and would like to install the 4 rail picatinny forearm. Looking to mount a bi-pod and need the 4 rail to do it. I have not purchased any tools or the forearm yet and would like to do the work myself. Any suggestions on brand/types I was also looking at the yankee hill front flip sights and was wondering what the rest of you thought of them??? I plan to mount a scope later on and that is why I am thinking about the flip sight, but a simple gas block with no sight might be just as good.