When you go to remove the original hand guard take off the rear sight first.  Next slide your cracked handguard down the barrel to the front sight.  Then very carefully remove hand guard so it does not become a two piece hand guard.

Don't ask me how I know.  I will start to cry and rant like a lunatic. :(

Wrap the hand guard in bubble wrap enough to fill an oatmeal box and place in same.