It's pretty easy actually. The stirrup, just take it off and wrap it with the LimbSaver wrap. On the wrap though, prior to starting, fold the strip in half and make a mark. As you're wrapping, you'll need to stretch the rubber some to get it to wrap the entire stirrup. When you hit the half way point, you should be half way through the wrap.
![Wink :wink:](./images/smilies/icon_wink.gif)
If not, unwrap and start again.
On foam filling the rail, I took everything off and out of mine, and then wrapped the rail with tape to keep the foam off of everywhere I didn't want it. Fill the 2 cavities of the rail and let it harden a few days. Take the tape off and start cutting/carving out the holes and area for the trigger assembly.
As enormous said, you'll never completely silence one. You can quieten them down to some extent, but you'll never get them down to a whisper.