Replace Objects?

[xMusicofmySoulx]

I'm making a Mario-style game in Alice, and I had been using cubes as bricks, but those are very difficult to orient correctly and it just occurred to me that it might be easier with squares. Is there a way to replace all of my cubes with squares, without having to do each one by hand? There are almost fifty of them, so any help would be greatly appreciated. Thank you!