I've had my AR about 6 months now and it is time to start changing it Right now it is as basic as you can get.

So my first step is going to be putting a free float hand guard on it. What I'm wondering is how hard is it to install one? I'm considering the Yankee Hill 4 rail rifle setup, with this can I leave my current front base on or do I need to remove it and replace it with a gas block that doesn't have a front sight on it? In general are there any special tools I'd need?