When tween AS is finished or at location do this

1

Hi,

First off im a real newbie with AS,
Recently i started tweening using Robert Penners AS Classes.
Wich are quite cool btw.

However i now want that when the animation reaches
a certain _x / _y value or at the end of the animation that it executes a removeMovieClip() and attaches a new one.

Code:

maincontainer.splash.start_btn.onPress = function() {
    new mx.transitions.Tween(maincontainer.splash.start_btn, "_y", mx.transitions.easing.Bounce.easeOut, 455, -600, 50);
    new mx.transitions.Tween(maincontainer.splash.mainbg_mc, "_y", mx.transitions.easing.Bounce.easeOut, 432, -600, 50);
    new mx.transitions.Tween(maincontainer.splash.menubar_mc, "_y", mx.transitions.easing.Bounce.easeOut, 432, -600, 25);
    }

To clarify when menubar_mc reaches y_ -600 it should execute the removeMovieClip();