Has anyone done this?  How do you get it to come out even at the top-- without deforming the diamond pattern or creating big spaces between the diamonds?  (Does that make sense?)

OK I just was searching this and I found the answer.  I guess it's not as hard as I was thinking.  I've always made my topsy-turvy's with angled sides (larger at the top than the bottom).  Now I see that they make pans for this and they have straight sides-- VOILA!