How do find the rightmost point of an ellipse?

[eobet]

Hello!

I wonder what the eqvivalent of an "extrude" is in Xara X? http://www.talkgraphics.com/images/smilies/smile.gif

As you see, I need the highlighted object at the bottom to align perfectly with the object at the top in the picture below.

Currently, the "3D" is achieved with a clone, a few taps of arrow keys down, and then using snap to object, I guessed the outer edges.