Right-align YUI3 menu bar items?

I work on a project that used to use YUI2 to power it's web interface. We use the menubar plugin, and had a couple of menus right aligned. We achieved this by adding float: right to the CSS for the <li> tags that surround the menu links themselves. This worked perfectly.

We have now upgraded to YUI3开发者_开发技巧, and this no longer works for some reason, and I have no idea why.

What is the correct way to right-align one or two menu items in YUI3?