I'd put them on asap...I waited a few weeks to do mine after I put more lift on and it didnt hurt anything but I was just driving around town. I would definitely put them on before you go wheeling at all. You can put hockey pucks in the front, I did mine in a few minutes with some 5 minute epoxy from wal mart. I used 3 regular pucks on each side and one practice puck each on top. The practice pucks are softer than the regular ones and soften it up considerably when bottoming out. For the rears, I just used the regular bump stops with a piece of square tubing to space them down.
I had a thread about it a few weeks ago, there are some different ideas that others suggested there.